### Reproduction steps Build libgit2 with mbedtls using the patch from #4173 Used this patch at https://anonscm.debian.org/git/collab-maint/libgit2.git/tree/debian/patches/use-mbedtls.patch and build it in a clean chroot without openssl. ### Expected behavior It should not add openssl as a dependency in .pc. ### Actual behavior The generated ibgit2.pc has openssl ``` prefix="/usr" libdir=${prefix}/lib/x86_64-linux-gnu includedir=${prefix}/include Name: libgit2 Description: The git library, take 2 Version: 0.27.0 Libs: -L${libdir} -lgit2 Libs.private: -lrt -lpthread -lhttp_parser -lssh2 Requires.private: openssl zlib Cflags: -I${includedir} ``` and makes build of other software using libgit2 to fail. See https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=899036 ### Version of libgit2 (release number or SHA1) 0.27.0 ### Operating system(s) tested Debian unstable/experimental.