msm: sensor: actuator: fix out of bound read for region params

Issue:
the region index is not validated against the region size.
this cause out-of-bound read on the KASAN kernel.

Fix:
Add restriction that region index smaller than region size.

Change-Id: I141bba45662769f0661c947fb642c2671578f32e
Signed-off-by: Mounika Reddy Tangirala <mtangi@codeaurora.org>