Active state requests are sent immediately to the RSC controller, while
sleep and wake state requests are cached in this driver to avoid taxing
the RSC controller repeatedly. The cached values will be sent to the
controller when the rpmh_flush() is called.

Generally, flushing is a system PM activity and may be called from the
system PM drivers when the system is entering suspend or deeper sleep
modes during cpuidle.

Also allow invalidating the cached requests, so they may be re-populated
again.
Signed-off-by: NLina Iyer <ilina@codeaurora.org>
[rplsssn: remove unneeded semicolon, address line over 80chars error]
Signed-off-by: NRaju P.L.S.S.S.N <rplsssn@codeaurora.org>
Reviewed-by: NEvan Green <evgreen@chromium.org>
Reviewed-by: NMatthias Kaehlcke <mka@chromium.org>
Signed-off-by: NAndy Gross <andy.gross@linaro.org>