Introduce avf_build_flags_cc cc_defaults

These are similar to avf_build_rust_build flags, but for cc_* soong
modules.

In the immediate future this will be used for flag guarding
virtcpu-freq related changes to platform.dts.

This patch also adds avf_build_flags_cc as cc_defaults to all our
existing cc_* soong modules

Test: builds
Bug: 284369518
Change-Id: I19152675802548cd9efba30a40bccdbb14867fe1
diff --git a/tests/benchmark/Android.bp b/tests/benchmark/Android.bp
index 31fe0f6..c31c929 100644
--- a/tests/benchmark/Android.bp
+++ b/tests/benchmark/Android.bp
@@ -34,6 +34,7 @@
 
 cc_library_shared {
     name: "MicrodroidBenchmarkNativeLib",
+    defaults: ["avf_build_flags_cc"],
     srcs: ["src/native/*.cpp"],
     local_include_dirs: ["src/native/include"],
     static_libs: [