media: seco-cec: declare ops as static const

As warned by smatch:

	drivers/media/platform/seco-cec/seco-cec.c:338:21:  warning: symbol 'secocec_cec_adap_ops' was not declared. Should it be static?

This struct should be static. Also, it is const, so declare it
as such.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>