mmc: sdhci-msm: add PM QoS voting

Add PM QoS voting mechanism to sdhci-msm driver for command queueing.
Two types of voting schemes are supported:
1) Vote for HW IRQ
2) Vote for a cpu group according to the request's designated cpu
Using PM QoS voting should benefit performance.

Change-Id: I8a20653eeb6348d5b442c846708d92c8fb64a8e9
Signed-off-by: Gilad Broner <gbroner@codeaurora.org>