nuc900fb: release correct mem region

We should be releasing "res->start" here.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Wan ZongShun <mcuos.com@gmail.com>
Cc: Wang Qiang <rurality.linux@gmail.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>