compiler-rt, libcxxabi, libcxx: Drop libstdc++ usage

The configure scripts for these libraries was relying on
listdc++ installation for passing working compiler checks.

Replace with "STATIC_LIBRARY" target for compiler-rt
and mark the compiler as working for libc++/libc++abi.

BUG=chromium:1159292
TEST=CQ

Change-Id: I43b92578835aad9cb0a5e8b126f3a3cf355d54f0
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/chromiumos-overlay/+/2594690
Tested-by: Manoj Gupta <manojgupta@chromium.org>
Auto-Submit: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Jian Cai <jiancai@google.com>
Commit-Queue: Manoj Gupta <manojgupta@chromium.org>
6 files changed