msm: camera: ife: Subscribe to error IRQs only on slave core

This change adds a check for slave core in dual IFE usecases
to avoid subscribing to SOF/EOF/EPOCH IRQs. We can use IRQs
from single core to drive our state machine. Error IRQs must
still be subscribed to as earlier.

CRs-Fixed: 2639855
Change-Id: I6aa6ab5b7e1049cd12f702da560b9b4a6ba9562b
Signed-off-by: Venkat Chinta <vchinta@codeaurora.org>