[PATCH] pmagb-b-fb: Fix a default clock frequency

Inspection of real hardware has revealed one of the clock frequencies known
to be supported by PMAGB-B hardware is off by 3kHz.  Following is a fix.
Please apply.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Acked-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>