In the CMake "CONFIGURE_FILE(<input> <output>)" command, the <input> path is treated relative to SOURCE dir, however the <output> patch is relative to BUILD dir.
Since the file has been copied to a wrong location, instead in-place updated as originally intended, the file that was later installed was the original unchanged file.
Resolves: #1873999, #1874446
Fix mariadb-pcdir.patch hunk
The upstream now defaults to the location we need, although the server pkgconfig file location is still NOT configurable.
The CMake INSTALL_PCDIR option affects only the client library pkgconfig file location.
