Check for openssl and libcrypto using pkg-config and don't build the
plugin if those are not available. Also, fix the CFLAGS/LIBS order
in Makefile.am and use the detected LIBS instead of hard-coding
-lcrypto in the Makefile.am. Should fix#601417.
Original commit message from CVS:
* ext/apexsink/Makefile.am:
Link against -lgcrpyto for RSA_new and RSA_free.
* ext/faac/gstfaac.c:
* ext/x264/gstx264enc.c:
Fix compiler warnings.