71f4218c1a
* Add -lkstat to the .pc for Solaris This fixes linking for projects that rely on pkg-config to generate the link line on Solaris. Test plan: Built the project locally on Solaris and verified -kstat appears in the .pc file ``` $ cat lib/pkgconfig/benchmark.pc | grep Libs.private Libs.private: -lpthread -lkstat ``` * Use BENCHMARK_PRIVATE_LINK_LIBRARIES