Revert commit v3.6.0-rc1~160^2 (try_compile: Honor
CMAKE_<LANG>_FLAGS_<CONFIG> changes, 2016-04-11). The behavior it
introduced can break projects that depend on the lack of such behavior.
We will have to introduce a policy or other mechanism to enable the
behavior in a compatible way. Simply revert it for now.
See issue #16174.