vout_macosx: remove misleading user-facing error message about Quartz Extreme...

vout_macosx: remove misleading user-facing error message about Quartz Extreme being unavailable (close #9777)

While it is strongly desirable to be present, the API behavior or the driver quality seem to have changed on OS X 10.9, so this alert is triggered way to often while video is actually being displayed just fine.

Log message is retained for debugging purposes.

modules/video_output/macosx.m

@@ -143,11 +143,8 @@ static int Open (vlc_object_t *this)
     if (!sys)
         return VLC_ENOMEM;
 
-    if (!CGDisplayUsesOpenGLAcceleration (kCGDirectMainDisplay)) {
+    if (!CGDisplayUsesOpenGLAcceleration (kCGDirectMainDisplay))
         msg_Err (this, "no OpenGL hardware acceleration found. this can lead to slow output and unexpected results");
-        dialog_Fatal (this, _("OpenGL acceleration is not supported on your Mac"), _("Your Mac lacks Quartz Extreme acceleration, which is required for video output. It will still work, but much slower and with possibly unexpected results."));
-    } else
-        msg_Dbg (this, "Quartz Extreme acceleration is active");
 
     vd->sys = sys;
     sys->pool = NULL;