power: qpnp-smbcharger: qpnp-fg: lower resume soc upon termination

Charging during a JEITA warm or cool condition will cause charge
termination before the fuel gauge hits 100%. If the PMIC is using fuel
gauge soc based resume of charging, it will just immediately begin to
start recharging.

Fix this by lowering the resume soc to the monotonic soc minus some
margin when the charger reaches full.

CRs-Fixed: 799673
Change-Id: Id56e6394777ecde7e8216ecdfccc4e46665f2ae4
Signed-off-by: Xiaozhe Shi <xiaozhes@codeaurora.org>