power: qpnp-smbcharger: add support for high current SDP/floating charger

Add support to configure high ICL for SDP chargers, this is useful in case
of SDP or floating chargers which supports high current.
If 'qcom,override-usb-current' property is present override and set ICL
based on current reported by the USB driver otherwise set to USB500 mode.

CRs-Fixed: 963417
Change-Id: I31304cd2a4e710f4e450e6ec5a4da90c50fdfc88
Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>