msm: ipa: Fix incorrect wakelock handling

With the current logic __pm_stay_awake is
called whenever wakelock ref cnt is non-zero
and released only when it is 0. Make a change
to acquire wakelock only when it is not held
previously and releasing time chaeck and
release it only if it is held previously.

Change-Id: I8c61c184506c705fd5866de8a606f642c5de3d5b
Acked-by: Chaitanya Pratapa <cpratapa@qti.qualcomm.com>
Signed-off-by: Utkarsh Saxena <usaxena@codeaurora.org>