staging: sm750fb: fixing function return with lock held

lynxfb_suspend() & lynxfb_resume() return on errors while holding
console_lock.

Adding 'goto' such that proper cleanups can be done before returning
from function and therefore console_lock can be released before
returning.

Signed-off-by: Prasant Jalan <prasant.jalan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>