cocoa: Fix invalid NSMenuItem selector in SDL_tray

SDL3/src/tray/cocoa/SDL_tray.m:511:98: error: undeclared selector 'menu:' [-Werror,-Wundeclared-selector]
  511 |         nsitem = [[NSMenuItem alloc] initWithTitle:[NSString stringWithUTF8String:label] action:_selector(menu:) keyEquivalent:_""];

src/tray/cocoa/SDL_tray.m

@@ -508,7 +508,7 @@ SDL_TrayEntry *SDL_InsertTrayEntryAt(SDL_TrayMenu *menu, int pos, const char *la
     if (label == NULL) {
         nsitem = [NSMenuItem separatorItem];
     } else {
-        nsitem = [[NSMenuItem alloc] initWithTitle:[NSString stringWithUTF8String:label] action:@selector(menu:) keyEquivalent:@""];
+        nsitem = [[NSMenuItem alloc] initWithTitle:[NSString stringWithUTF8String:label] action:@selector(menu) keyEquivalent:@""];
         [nsitem setEnabled:((flags & SDL_TRAYENTRY_DISABLED) ? FALSE : TRUE)];
         [nsitem setState:((flags & SDL_TRAYENTRY_CHECKED) ? NSControlStateValueOn : NSControlStateValueOff)];
         [nsitem setRepresentedObject:[NSValue valueWithPointer:entry]];