charger: suspend enable in charger mode

To reduce power consumption after charging completion, enable suspend when LCD
is turned off.

Bug: 7429504
Change-Id: I34731dc392661c9051a20cea74f70d94a8aaeb42
Signed-off-by: Iliyan Malchev <malchev@google.com>
charger: Do not suspend when disconnecting from charger

The device should be power off when disconnecting from charger.
If the device enter to suspend, the device couldn't handle the power off
process. So the device shouldn't suspend to handle the power off at that time

Bug: 7429504
Change-Id: I9a0a60e53f315cd83550dc730a33bc7bd464ef67