The script was looking for the wrong header file. Instead of look for
yajl_parse.h it was looking for yajl.h. Originally reported by
@rpfilomeno at #804.
Seems like curl versions older than 7.34.0 does not have support for
`CURL_SSLVERSION_TLSv1_2'. In this cases, using CURL_SSLVERSION_TLSv1
which was added at version 7.9.2. ModSecurity demands a curl version
newer than 7.15.1.
Using apr-util installed by Macports results in build failure because apr-util uses BerkeleyDB that MacPorts installs into a subdir of $prefix/lib and $prefix/include (so that multiple versions of BerkeleyDB can be installed simultaneously). apu-1-config's --ldflags output includes the -L/path/to/bdb that's needed.
Now searching for yajl using find_yajl.m4 macro file instead
of using pkg-config directly. If YAJL was not found or if it
was disabled in the configure phase, the code will be compiled
without JSON support.
