soc: swr: Release resource lock when not needed

Resource lock should not be held while doing bank
switch as bank switch requires interrupt handling
which needs access to the resource lock.

Change-Id: Ic17178c7e6f16a7db91da6577ed2ce70c9c9f084
Signed-off-by: Karthikeyan Mani <kmani@codeaurora.org>