media: rkisp1: Drop parentheses and fix indentation in rkisp1_probe()

Fix a small indentation issue to increase code readability, and drop
unneeded parentheses.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>