Fix the build with LibreSSL.

LibreSSL does not define SSL_CTRL_SET_CURVES, so check for the macro's
existence before using it.

I'm committing this mostly to get it into the 2016Q3 branch so it lives a bit
longer: starting with Qt 5.6, upstream explicitly does not support LibreSSL and
fails at configuration time if it is detected (the rationale being that they do
not want to make the OpenSSL backend code even more confusing with additional
checks and code paths for LibreSSL; patches adding a separate LibreSSL backend
are more than welcome, but someone needs to write the code and maintain it).

PORTREVISION is not being bumped because the LibreSSL build was simply broken
before, and the patch does not change anything for OpenSSL users.

PR:		211832
Submitted by:	matthew@reztek.cz
MFH:		2016Q3

0 files changed, 0 insertions, 0 deletions