power: qpnp-smbcharger: Remove a redundant find_first_bit

Currently get_usb_type_name() and get_usb_supply_type() both uses
the find_first_bit() to determine type name and supply type. Instead
of using find_first_bit multiple times, call it once by using
get_type() and use at multiple places.

Change-Id: Ie8bdd0523c2d32d306a1eaff3035687eec2282fd
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>