Osx: Do not use CROSSTOOL to select cc_toolchain
Osx: Do not use CROSSTOOL to select cc_toolchain

This is a preparation for flipping
--incompatible_disable_cc_toolchain_label_from_crosstool_proto, which will stop
reading default_toolchain fields from the crosstool and will rely on
cc_toolchain_suite.toolchains containing entries for cpu without compiler.

RELNOTES: None.
PiperOrigin-RevId: 216717701

perezd/bazel,cushon/bazel,meteorcloudy/bazel,twitter-forks/bazel,werkt/bazel,dslomov/bazel-windows,bazelbuild/bazel,katre/bazel,ButterflyNetwork/bazel,meteorcloudy/bazel,twitter-forks/bazel,meteorcloudy/bazel,ulfjack/bazel,ButterflyNetwork/bazel,werkt/bazel,aehlig/bazel,werkt/bazel,katre/bazel,dslomov/bazel,twitter-forks/bazel,perezd/bazel,twitter-forks/bazel,aehlig/bazel,dslomov/bazel,safarmer/bazel,dslomov/bazel,perezd/bazel,dslomov/bazel,aehlig/bazel,safarmer/bazel,perezd/bazel,meteorcloudy/bazel,twitter-forks/bazel,ulfjack/bazel,katre/bazel,cushon/bazel,dslomov/bazel-windows,cushon/bazel,werkt/bazel,akira-baruah/bazel,safarmer/bazel,davidzchen/bazel,dslomov/bazel-windows,werkt/bazel,aehlig/bazel,cushon/bazel,bazelbuild/bazel,davidzchen/bazel,bazelbuild/bazel,ulfjack/bazel,perezd/bazel,werkt/bazel,akira-baruah/bazel,safarmer/bazel,meteorcloudy/bazel,perezd/bazel,davidzchen/bazel,bazelbuild/bazel,safarmer/bazel,meteorcloudy/bazel,katre/bazel,davidzchen/bazel,twitter-forks/bazel,dslomov/bazel,davidzchen/bazel,aehlig/bazel,bazelbuild/bazel,ButterflyNetwork/bazel,akira-baruah/bazel,ulfjack/bazel,ButterflyNetwork/bazel,safarmer/bazel,ulfjack/bazel,dslomov/bazel,meteorcloudy/bazel,aehlig/bazel,ulfjack/bazel,akira-baruah/bazel,aehlig/bazel,dslomov/bazel-windows,ButterflyNetwork/bazel,cushon/bazel,akira-baruah/bazel,twitter-forks/bazel,perezd/bazel,dslomov/bazel-windows,cushon/bazel,ulfjack/bazel,dslomov/bazel,ButterflyNetwork/bazel,bazelbuild/bazel,akira-baruah/bazel,katre/bazel,davidzchen/bazel,davidzchen/bazel,dslomov/bazel-windows,katre/bazel