msm: camera: isp: Unlock spinlock in fatal error for CSID

While handling CSID fatal error, spin lock is not getting released.
Release the lock before handling the error.

Change-Id: I6e72206cadb3a979c8734d25c7bf1c1e020a5dc9
CRs-fixed: 2672737
Signed-off-by: Gaurav Jindal <gjindal@codeaurora.org>