Fix build warnings when CONFIG_PM is not set/enabled:

../drivers/media/platform/marvell-ccic/mmp-driver.c:324:12: warning: 'mmpcam_runtime_suspend' defined but not used [-Wunused-function]
  324 | static int mmpcam_runtime_suspend(struct device *dev)
../drivers/media/platform/marvell-ccic/mmp-driver.c:310:12: warning: 'mmpcam_runtime_resume' defined but not used [-Wunused-function]
  310 | static int mmpcam_runtime_resume(struct device *dev)
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>