Modify unix C++ toolchain autoconfiguration features to pass flags to lto-index actions as well
Modify unix C++ toolchain autoconfiguration features to pass flags to lto-index actions as well

https://github.com/bazelbuild/bazel/issues/6791

RELNOTES: None.
PiperOrigin-RevId: 256666054

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