ANDROID: GKI: power_supply: Add local extensions of string property names properly

For displaying local extensions of properties in string format,
add them between MODEL_NAME and SERIAL_NUMBER. Otherwise, those
properties would be represented as integer.

Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
(cherry picked from commit ee0f7c41453f8b9c71f3ffb0c124f6ea5708513e)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 150789066
Change-Id: Iddb34d7ee6f520b789bc2e085ada4053343538f0