msm : camera : Change register value to get 15fps in ZSL mode

Update ZSL (Zero Shutter Lag) fps to 15fps, VFE gets
sufficient AXI bandwidth to support this frame rate

Change-Id: Ied6c0185c0b45c2b7a0bf9b239b62fd1b2e12471
Signed-off-by: Aditya Jonnalagadda <ajonnala@codeaurora.org>