SDL: Fixed building with older macOS SDK

From a3ce0d03e36786e762d6541b5754d6a771962e67 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Wed, 17 May 2023 13:32:21 -0700
Subject: [PATCH] Fixed building with older macOS SDK

---
 src/video/cocoa/SDL_cocoaclipboard.m | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/video/cocoa/SDL_cocoaclipboard.m b/src/video/cocoa/SDL_cocoaclipboard.m
index c54a76c18e55..1fa7fff32629 100644
--- a/src/video/cocoa/SDL_cocoaclipboard.m
+++ b/src/video/cocoa/SDL_cocoaclipboard.m
@@ -25,6 +25,10 @@
 #include "SDL_cocoavideo.h"
 #include "../../events/SDL_clipboardevents_c.h"
 
+#if MAC_OS_X_VERSION_MAX_ALLOWED < 101300
+typedef NSString *NSPasteboardType; /* Defined in macOS 10.13+ */
+#endif
+
 @interface Cocoa_PasteboardDataProvider : NSObject<NSPasteboardItemDataProvider>
 {
     SDL_ClipboardDataCallback m_callback;