media: st-mipid02: add support of pixel clock polarity

Add support of pixel clock polarity.

Signed-off-by: Hugues Fruchet <hugues.fruchet@foss.st.com>
Reviewed-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>