msm: vidc: Add support to CVP skip ratio

Introduced CVP skip ratio property to indicate the number of
buffers skipped for CVP processing. This serves as a hint to Video
firmware to know the number of frames for which CVP metadata has to be
reused from earlier frame to which CVP metadata was sent

Change-Id: I58ad5daf9a9c6ae7a0aa48e3bd1d60e7dc9229e6
Signed-off-by: Akshata Sahukar <asahukar@codeaurora.org>