fix release build

git-svn-id: http://skia.googlecode.com/svn/trunk@719 2bbb7eff-a529-9590-31e7-b0007b416f81

xcode/core/core.xcodeproj/project.pbxproj

@@ -744,10 +744,7 @@
 		1DEB91F108733DB70010E9CD /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
-				ARCHS = (
-					ppc,
-					i386,
-				);
+				ARCHS = "$(NATIVE_ARCH)";
 				GCC_ENABLE_CPP_EXCEPTIONS = NO;
 				GCC_ENABLE_CPP_RTTI = NO;
 				GCC_OPTIMIZATION_LEVEL = 2;