asoc: mbhc: fix for fake ins irq

Check for in2p clamp state in insertion irq
and ignore the interrupt if the clamp is already
set, which means the mechanical removal is about
to happen next.

Change-Id: I55691d427cf07d5b61862b6dbd39f3ec34d873e5
Signed-off-by: Karthikeyan Mani <kmani@codeaurora.org>