msm: camera: isp: Enable CGC for GIC, pedestal and GTM

Enable Clock gating for GIC, pedestal and GTM blocks. This helps to
save power since hardware gates clock during blanking period.

Change-Id: I9c2c2c7c8d4c4ef935637d039620f939c32d7fbb
Signed-off-by: Sreesudhan Ramakrish Ramkumar <srramku@codeaurora.org>