cocoa: Change Caps Lock behavior to toggle instead of locking

It currently behaves like a locking key which is pressed
when Caps Lock is enabled and released when disabled. This
means that apps that trigger events on Caps Lock key down will
only fire these events every other time Caps Lock is pressed.

src/video/cocoa/SDL_cocoawindow.m

@@ -912,11 +912,9 @@ SetWindowStyle(SDL_Window * window, NSUInteger style)
        keypresses; it won't toggle the mod state if you send a keyrelease.  */
     const SDL_bool osenabled = ([theEvent modifierFlags] & NSEventModifierFlagCapsLock) ? SDL_TRUE : SDL_FALSE;
     const SDL_bool sdlenabled = (SDL_GetModState() & KMOD_CAPS) ? SDL_TRUE : SDL_FALSE;
-    if (!osenabled && sdlenabled) {
-        SDL_ToggleModState(KMOD_CAPS, SDL_FALSE);
-        SDL_SendKeyboardKey(SDL_RELEASED, SDL_SCANCODE_CAPSLOCK);
-    } else if (osenabled && !sdlenabled) {
+    if (osenabled ^ sdlenabled) {
         SDL_SendKeyboardKey(SDL_PRESSED, SDL_SCANCODE_CAPSLOCK);
+        SDL_SendKeyboardKey(SDL_RELEASED, SDL_SCANCODE_CAPSLOCK);
     }
 }
 - (void)keyDown:(NSEvent *)theEvent