msm: ipa: add support for AP suspend in rmnet_ipa

When AP suspend is triggered, there is a need to immediately release the
WWAN0_PROD entity, which enables clock gating IPA HW.

Change-Id: I13df22b5abf48e5de6349d309abb0810c6dc9c7f
Signed-off-by: Gidon Studinski <gidons@codeaurora.org>
Signed-off-by: Ravit Katzav <rkatzav@codeaurora.org>