msm: camera: Fix spinlock init issue

xbar spinlock is used by VFE31 driver without initializing
it. Update the driver to initialize xbar lock at
init function to avoid kernel crash with camera.

Change-Id: Ib8ddfa26ec53a75f989371a35746dabad96e3670
Signed-off-by: Suresh Vankadara <svankada@codeaurora.org>