msm: camera: Fix the VPE state machine to avoid multiple VPE disable.

Patch to ensure VPE state machine is handled properly in case of
monkey runs. This is a corner case where vpe disable got triggered
twice.

CRs-Fixed: 330166
Change-Id: I69144204dd491eb0f2f9f9c9c0a987e527449d03
Signed-off-by: Azam Sadiq Pasha Kapatrala Syed <akapatra@codeaurora.org>