msm: ipa: add proxy ipa clock vote for Modem on SSR

This is to prevent IPA power-collapse until Modem has
loaded the IPA uC on a warm-boot (After Modem SSR occured).
Additionally, in case SSR has occured and the uC hasn't
been loaded yet, AP needs to assert in order to prevent the IPA
from entering an unrecoverable state (As the Modem relies on AP
to reset the pipes properly).

CRs-fixed: 726901
Change-Id: Ibb79cef4a16fdc9e18ede854a14e65f4f248761d
Acked-by: David Arinzon <darinzon@qti.qualcomm.com>
Signed-off-by: Sivan Reinstein <sivanr@codeaurora.org>