drivers/video/mb862xx/mb862xxfbdrv.c needs uaccess.h

alpha allmodconfig:

drivers/video/mb862xx/mb862xxfbdrv.c: In function 'mb862xxfb_ioctl':
drivers/video/mb862xx/mb862xxfbdrv.c:323: error: implicit declaration of function 'copy_to_user'
drivers/video/mb862xx/mb862xxfbdrv.c:327: error: implicit declaration of function 'copy_from_user'

Cc: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>