ion: Drop cache operation after zeroing

At one time, the zeroing algorithm used a mixture of
cached and uncached mappings which necessitated an extra
cache operation afterwards. The zeroing algorithm has been
simplified so the cache operation is no longer required if
the mapping used for zeroing matches the cache status of
the buffer (cached or not). Remove the cache operation and
use appropriate page protections instead.

Change-Id: I7d3596ed503811818782e77a0f3f7f63b1456d70
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
PM / devfreq: governor_bw_hwmon: Add suspend/resume support

Some devfreq devices using this governor might need suspend/resume support.
When suspended, those devices won't need any bandwidth votes and there is
no point in monitoring their bandwidth either.

Therefore, upon suspend, vote for zero bandwidth and stop the HW monitor.
Upon resume, vote for the previous bandwidth and start the HW monitor.

Change-Id: I318449995d714959f0ebfe91961bc23fa8edbd04
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>

PM / devfreq: devbw: Add suspend/resume APIs

Absence of traffic is guaranteed when the device sitting behind a devbw
device is suspended. In such cases, it is a waste of power to make non-zero
bandwidth votes or to scale the devbw device. So, provide APIs to
suspend/resume the devbw device as needed.

Change-Id: Id58072aec7a9710eb917f248d9b9bd08d3a1ec6a
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>