[media] lirc_dev: add some __user annotations

Sparse complains because there are no __user annotations.

drivers/media/rc/lirc_dev.c:156:27: warning:
	incorrect type in initializer (incompatible argument 2 (different address spaces))
drivers/media/rc/lirc_dev.c:156:27:    expected int ( *read )( ... )
drivers/media/rc/lirc_dev.c:156:27:    got int ( extern [toplevel] *<noident> )( ... )

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>