power: pm8921-charger: disable AICL when charging is disabled

If charging is disabled the VCHG line will see a drop in input
voltage regulation and the VIN_ACTIVE bit will be set.

To avoid incorrectly changing the USB input current limit disable the
adjustments made by the AICL algorithms if charging is disabled.

CRs-Fixed: 380478
Change-Id: I2bf31a23199f942a9ac843b9940a0f7377256238
Signed-off-by: David Keitel <dkeitel@codeaurora.org>