media: imx-jpeg: Apply clk_bulk api instead of operating specific clk

using the api of clk_bulk can simplify the code.
and the clock of the jpeg codec may be changed,
the clk_bulk api can be compatible with the future change.

Fixes: 4c2e5156 ("media: imx-jpeg: Add pm-runtime support for imx-jpeg")
Signed-off-by: Ming Qian <ming.qian@nxp.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>