Enable MLGO inliner optimization for optimize_for_size cases

This helps reduce binary size for these projects by ~3%.

Test: presubmit
Bug: 342090838
Change-Id: Ie1e0586ddf5f40aa1e81fc2628a6499093de9699

cc/compiler.go

@@ -695,6 +695,7 @@ func (compiler *baseCompiler) compilerFlags(ctx ModuleContext, flags Flags, deps
 
 	if ctx.optimizeForSize() {
 		flags.Local.CFlags = append(flags.Local.CFlags, "-Oz")
+		flags.Local.LdFlags = append(flags.Local.LdFlags, "-Wl,-mllvm,-enable-ml-inliner=release")
 	}
 
 	// Exclude directories from manual binder interface allowed list.