media: ti-vpe: cal: Mark cal_camerarx_media_ops with static keyword

Fix the following sparse warning:

drivers/media/platform/ti-vpe/cal-camerarx.c:783:32: warning: symbol 'cal_camerarx_media_ops' was not declared. Should it be static?

Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>