SDL: SDL_cocoamodes.m: fix build against older SDKs.

From ea0bca573da796268900e53d74541dfe279bb662 Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Tue, 11 Jan 2022 14:56:56 +0300
Subject: [PATCH] SDL_cocoamodes.m: fix build against older SDKs.

Fixes https://github.com/libsdl-org/SDL/issues/5208
---
 src/video/cocoa/SDL_cocoamodes.m | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/video/cocoa/SDL_cocoamodes.m b/src/video/cocoa/SDL_cocoamodes.m
index e8ce12d868d..7d19030b219 100644
--- a/src/video/cocoa/SDL_cocoamodes.m
+++ b/src/video/cocoa/SDL_cocoamodes.m
@@ -40,6 +40,9 @@
 #ifndef MAC_OS_X_VERSION_10_13
 #define NSAppKitVersionNumber10_12 1504
 #endif
+#if (IOGRAPHICSTYPES_REV < 40)
+#define kDisplayModeNativeFlag 0x02000000
+#endif
 
 
 static void