power: smb135x-charger: Add support to disable charger-inhibit feature

The charger inhibit option prevents battery charging upon insertion of
charger when battery voltage is above the programmed inhibit threshold.

Disable charger-inhibit based on device-tree flag to always enable
charging on charger insertion.

CRs-Fixed: 703710
Change-Id: Ib09b5afbdc3f538c3d4c51db75ad6d2ce6dbaa86
Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>