[media] media: marvell-ccic: use devm to release clk

This patch uses devm to release the clks instead of releasing
manually.
And it adds enable/disable mipi_clk when getting its rate.

Signed-off-by: Libin Yang <lbyang@marvell.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>