power: qpnp-smb2: Unset ONLINE for UNKNOWN USB charger type

Currently, USB power_supply POWER_SUPPLY_PROP_ONLINE property will be
set if the charger type is POWER_SUPPLY_TYPE_UNKNOWN which is not
expected. Unset ONLINE for UNKNOWN USB charger type.

CRs-Fixed: 2065139
Change-Id: Ibc40ee62b2d95c319a7fe34b17813c2b57518f67
Signed-off-by: Fenglin Wu <fenglinw@codeaurora.org>