Patch to build SDL2 with OS X 10.9 SDK

3rdparty/Makefile

@@ -55,6 +55,7 @@ SDL2 = SDL2-$(SDL2VER)
 SDL2ARCH = $(SDL2).tar.gz
 SDL2URL = https://www.libsdl.org/release/$(SDL2ARCH)
 SDL2SHA256 = 349268f695c02efbc9b9148a70b85e58cefbbf704abd3e91be654db7f1e2c863
+SDL2PATCHES = SDL2-NSOSVersion.patch
 SDL2DEVEL = SDL2-devel-$(SDL2VER)-mingw.tar.gz
 SDL2DEVELURL = https://www.libsdl.org/release/$(SDL2DEVEL)
 SDL2DEVELPATCH = SDL2-devel.patch

3rdparty/SDL2-NSOSVersion.patch

@@ -0,0 +1,16 @@
+--- SDL2-2.0.12.orig/src/video/cocoa/SDL_cocoawindow.m	2020-03-11 02:36:18.000000000 +0100
++++ SDL2-2.0.12/src/video/cocoa/SDL_cocoawindow.m	2020-12-10 23:14:27.000000000 +0100
+@@ -1813,6 +1813,13 @@
+            This is no longer needed as of Mac OS X 10.15, according to bug 4822.
+          */
+         NSProcessInfo *processInfo = [NSProcessInfo processInfo];
++#if MAC_OS_X_VERSION_MAX_ALLOWED < 101000 /* NSOperatingSystemVersion added in the 10.10 SDK */
++        typedef struct {
++            NSInteger majorVersion;
++            NSInteger minorVersion;
++            NSInteger patchVersion;
++        } NSOperatingSystemVersion;
++#endif
+         NSOperatingSystemVersion version = { 10, 15, 0 };
+         if (![processInfo respondsToSelector:@selector(isOperatingSystemAtLeastVersion:)] ||
+             ![processInfo isOperatingSystemAtLeastVersion:version]) {