[PATCH] Recognize video=gx1fb:... option

Juergen Beisert reported that the following option doesn't work for him

	video=gx1fb:1024x768-16@60

though sisfb was able to parse similar option correctly.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: James Simmons <jsimmons@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>