soundwire: exit from pm function for LPASS HW Core fails

Before proceeding with handling soundwire pm functions
check return value of vote for LPASS HW core and handle
error scenarios.

Change-Id: I4f48c93919a75ebbb072123a12306137118699d0
Signed-off-by: Karthikeyan Mani <kmani@codeaurora.org>