Add rust toolchains

Signed-off-by: Ravago Jones <ravagojones@gmail.com>
Change-Id: I5f36ff152b01bbb628dea45175294cf7f52bb15f
diff --git a/tools/cpp/BUILD b/tools/cpp/BUILD
index 17f218e..6ff661a 100644
--- a/tools/cpp/BUILD
+++ b/tools/cpp/BUILD
@@ -76,6 +76,7 @@
     srcs = [
         ":flags_compiler_inputs",
         "//tools/cpp/arm-frc-linux-gnueabi:as",
+        "//tools/cpp/arm-frc-linux-gnueabi:libs",
         "//tools/cpp/arm-frc-linux-gnueabi:tool-wrappers",
         "@arm_frc_linux_gnueabi_repo//:compiler_pieces",
     ],