pm process should be done by chip specific, but we can provide a standard
flow, then vendor & chip can only focus on handle different state change.
Signed-off-by: buxiasen <buxiasen@xiaomi.com>
only when first time change state can hold WFI for enough time thresh,
allow second time goto target state,
suitable for the case when wakeup from sleep too slow, etc.
Signed-off-by: buxiasen <buxiasen@xiaomi.com>