Add debug and release cflags

Add debug: { cflags: [...] } and release: { cflags: [...] }.
For now it always takes the release cflags, later a per-module
debug selector will allow using the debug cflags.

Change-Id: I40bc68267287db901e47e74983d0d61fda2b9367
diff --git a/cc/cc.go b/cc/cc.go
index 8abfae7..d562421 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -200,6 +200,13 @@
 
 	// Set for combined shared/static libraries to prevent compiling object files a second time
 	SkipCompileObjs bool `blueprint:"mutated"`
+
+	Debug struct {
+		Cflags []string `android:"arch_variant"`
+	} `android:"arch_variant"`
+	Release struct {
+		Cflags []string `android:"arch_variant"`
+	} `android:"arch_variant"`
 }
 
 type unusedProperties struct {
@@ -371,6 +378,9 @@
 		ctx.ModuleErrorf("%s", err)
 	}
 
+	// TODO: debug
+	flags.cFlags = append(flags.cFlags, c.properties.Release.Cflags...)
+
 	if arch.HostOrDevice.Host() {
 		// TODO: allow per-module clang disable for host
 		flags.clang = true