(OSX) Add CROSS_COMPILE rules

Makefile

@@ -67,15 +67,22 @@ else ifeq ($(platform),osx)
    else ifeq ($(shell uname -p),arm)
 	MINVERSION =
    endif
-	ifndef ($(NOUNIVERSAL))
-		CFLAGS  += $(ARCHFLAGS)
-		CXXFLAGS  += $(ARCHFLAGS)
-		LDFLAGS += $(ARCHFLAGS)
-		MINVERSION=
-	endif
 
         fpic += $(MINVERSION)
 
+   ifeq ($(CROSS_COMPILE),1)
+		TARGET_RULE   = -target $(LIBRETRO_APPLE_PLATFORM) -isysroot $(LIBRETRO_APPLE_ISYSROOT)
+		CFLAGS   += $(TARGET_RULE)
+		CPPFLAGS += $(TARGET_RULE)
+		CXXFLAGS += $(TARGET_RULE)
+		LDFLAGS  += $(TARGET_RULE)
+   endif
+
+	CFLAGS  += $(ARCHFLAGS)
+	CXXFLAGS  += $(ARCHFLAGS)
+	LDFLAGS += $(ARCHFLAGS)
+
+
 # iOS
 else ifneq (,$(findstring ios,$(platform)))