power: qpnp-vm-bms: Notify userspace of every single SOC change

The SOC linearity logic does not notify the intermediate
SOC points if the SOC updates are not linear. Fix this by
calling power_supply_changed for every SOC change.

CRs-Fixed: 726493
Change-Id: Iefa6699c0db08006cf4e4ff3a8d2bdb46f56925f
Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>