* Rename Python2 functions to generic Python ones [1]
* Add support for FreeBSD

[1] Obtained from:

https://gitlab.archlinux.org/archlinux/packaging/packages/qt5-webengine/-/raw/main/qt5-webengine-python3.patch?ref_type=heads

--- src/buildtools/configure.json.orig	2023-11-09 12:28:27 UTC
+++ src/buildtools/configure.json
@@ -147,7 +147,8 @@
                     "int id = 0;",
                     "fre2.Add(s, {}, &id);",
                     "const RE2 &re2 = fre2.GetRE2(id);"
-                ]
+                ],
+                "qmake" : "CONFIG += c++1z"
             },
             "headers": "re2/filtered_re2.h",
             "sources": [
@@ -316,9 +317,9 @@
             "label": "system ninja",
             "type": "detectNinja"
         },
-        "webengine-python2": {
-            "label": "python2",
-            "type": "detectPython2",
+        "webengine-python": {
+            "label": "python",
+            "type": "detectPython",
             "log": "location"
         },
         "webengine-winversion": {
@@ -385,7 +386,7 @@
     "features": {
         "webengine-core-support": {
             "label": "Support Qt WebEngine Core",
-            "condition": "(config.linux || config.win32 || config.macos)
+            "condition": "(config.unix || config.win32 || config.macos)
                          && !config.static
                          && module.gui
                          && features.webengine-submodule
@@ -395,24 +396,24 @@
                          && features.webengine-gperf
                          && features.webengine-bison
                          && features.webengine-flex
-                         && features.webengine-python2
+                         && features.webengine-python
                          && features.webengine-nodejs
                          && (!config.sanitizer || features.webengine-sanitizer)
-                         && (!config.linux || features.pkg-config)
-                         && (!config.linux || features.webengine-host-pkg-config)
+                         && (!config.unix || features.pkg-config)
+                         && (!config.unix || features.webengine-host-pkg-config)
                          && (!config.linux || features.webengine-system-glibc)
-                         && (!config.linux || features.webengine-system-khr)
-                         && (!config.linux || features.webengine-system-nss)
-                         && (!config.linux || features.webengine-system-dbus)
-                         && (!config.linux || features.webengine-system-fontconfig)
-                         && (!config.linux || !features.pkg-config || !features.xcb || features.webengine-ozone-x11)
+                         && (!config.unix || features.webengine-system-khr)
+                         && (!config.unix || features.webengine-system-nss)
+                         && (!config.unix || features.webengine-system-dbus)
+                         && (!config.unix || features.webengine-system-fontconfig)
+                         && (!config.unix || !features.pkg-config || !features.xcb || features.webengine-ozone-x11)
                          && (!config.win32 || features.webengine-win-compiler64)
                          && (!config.win32 || features.webengine-winversion)",
             "output": [ "privateFeature" ]
         },
         "webengine-qtpdf-support": {
             "label": "Support Qt Pdf",
-            "condition": "(config.linux || config.win32 || config.macos || config.ios)
+            "condition": "(config.unix || config.win32 || config.macos || config.ios)
                          && module.gui
                          && features.webengine-submodule
                          && features.webengine-nowhitespace
@@ -421,10 +422,10 @@
                          && features.webengine-gperf
                          && features.webengine-bison
                          && features.webengine-flex
-                         && features.webengine-python2
+                         && features.webengine-python
                          && (!config.sanitizer || features.webengine-sanitizer)
-                         && (!config.linux || features.pkg-config)
-                         && (!config.linux || features.webengine-host-pkg-config)
+                         && (!config.unix || features.pkg-config)
+                         && (!config.unix || features.webengine-host-pkg-config)
                          && (!config.win32 || features.webengine-winversion)",
             "output": [ "privateFeature" ]
         },
@@ -444,12 +445,12 @@
             "autoDetect": "features.private_tests",
             "output": [ "privateFeature" ]
         },
-        "webengine-python2": {
-            "label": "python2",
-            "condition": "tests.webengine-python2",
+        "webengine-python": {
+            "label": "python",
+            "condition": "tests.webengine-python",
             "output": [
                 "privateFeature",
-                { "type": "varAssign", "name": "QMAKE_PYTHON2", "value": "tests.webengine-python2.location" }
+                { "type": "varAssign", "name": "QMAKE_PYTHON", "value": "tests.webengine-python.location" }
             ]
         },
         "webengine-gperf": {