[gl/gles] - remove annoying kai toast in videofilter fallback case

This removes the totally superfluous kai toast when falling back to bilinear scaling:

"Failed to init video filters/scalers, falling back to bilinear scaling".

Some mac users are hitting that problem. We were not able to reproduce (we don't have that hardware constellation) - so no way to really get the cause of the issue. But as this error is already logged into the log file and the files are playing fine with the fallback - there is really no reason to annoy users with this toast.


For reference:

http://forum.xbmc.org/showthread.php?tid=184026