power: supply: qcom: Add support to make SMB5 charger GKI compliant

SMB5 charger drivers and their helper files use several power supply
properties on msm-4.19 which cannot be supported on msm-5.4 due to the
need for GKI compliance. Add support for main charger to register
as an IIO device with individual channels under it corresponding to
missing power supply properties from msm-4.19.

Change-Id: I7182160258fa2ebd4af36b0531b11d988cffdbd3
Signed-off-by: Jishnu Prakash <jprakash@codeaurora.org>