cm_cxx_features: Ignore distcc warnings
Filter out warnings of distcc which does not provide information about compiler feature availability.
Resolves: #22573 (closed)
Upstreaming of Gentoo Linux patch: https://gitweb.gentoo.org/repo/gentoo.git/tree/dev-build/cmake/files/cmake-3.27.0_rc1-0006-Filter-out-distcc-warnings-to-avoid-confusing-CMake.patch
Gentoo bug: https://bugs.gentoo.org/691544
Topic-rename: cxx-checks-distcc
Edited by Brad King