clk: qcom: Add video clock driver for SM6150

Add support for the video clock controller found on SM6150
based devices. This would allow video device drivers to
probe and control their clocks.

Change-Id: Iffccc48d642d291db2133092cf19d4a726f25c99
Signed-off-by: Veera Vegivada <vvegivad@codeaurora.org>