SDL: Fixed building with 10.9 SDK

From 4d66501736d3c283f34ff950f5f0e3d52b24f5e4 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Sun, 24 Jul 2022 18:04:26 -0700
Subject: [PATCH] Fixed building with 10.9 SDK

Fixes https://github.com/libsdl-org/SDL/issues/5954
---
 src/video/cocoa/SDL_cocoamouse.m | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/video/cocoa/SDL_cocoamouse.m b/src/video/cocoa/SDL_cocoamouse.m
index 0239972ba8c..fcee0a738c0 100644
--- a/src/video/cocoa/SDL_cocoamouse.m
+++ b/src/video/cocoa/SDL_cocoamouse.m
@@ -117,7 +117,7 @@ + (NSCursor *)invisibleCursor
     const int frames = (int)[[info valueForKey:@"frames"] integerValue];
     NSCursor *cursor;
     NSImage *image = [[NSImage alloc] initWithContentsOfFile:[cursorPath stringByAppendingPathComponent:@"cursor.pdf"]];
-    if ((image == nil) || (image.valid == NO)) {
+    if ((image == nil) || (image.isValid == NO)) {
         return [NSCursor performSelector:fallback];
     }