Move toolchain and global variables into separate package

Move all of the configuration into a cc/config package

Change-Id: If56fc7242062ed1ce3cb297f78a1e0ef7537373c

cc/util.go

@@ -101,25 +101,6 @@ func flagsToBuilderFlags(in Flags) builderFlags {
 	}
 }
 
-func copyVariantFlags(m map[string][]string) map[string][]string {
-	ret := make(map[string][]string, len(m))
-	for k, v := range m {
-		l := make([]string, len(m[k]))
-		for i := range m[k] {
-			l[i] = v[i]
-		}
-		ret[k] = l
-	}
-	return ret
-}
-
-func variantOrDefault(variants map[string]string, choice string) string {
-	if ret, ok := variants[choice]; ok {
-		return ret
-	}
-	return variants[""]
-}
-
 func addPrefix(list []string, prefix string) []string {
 	for i := range list {
 		list[i] = prefix + list[i]