ANDROID: power_supply: Use fwnode to retrieve psy array from phandle

Upstream commit f368f87b ("power: supply: core: convert to fwnnode")
replaced all instances of device nodes in power supply with
fwnodes. Update the helper introduced by commit dea1a925 ("ANDROID:
power_supply: Add a helper function to retrieve psy array from phandle")
to be more in-line with upstream and remove its empty definition because
it no longer needs to be guarded by CONFIG_OF. We maintain this helper
as an out-of-tree patch because it was rejected upstream for not having
a mainline user.

Signal to vendors that this implementation has changed by renaming this
function from "power_supply_get_by_phandle_array" to
"power_supply_get_by_reference_array", using the naming convention from
commit 370643f4 ("power: supply: core: rename power_supply_get_by_phandle power_supply_get_by_reference").

This change fixes the following kernelci build issue caused by removing
the if CONFIG_OF guards around the original helper function:

drivers/power/supply/power_supply_core.c:590:5: error: conflicting types for ‘power_supply_get_by_phandle_array’; have ‘int(struct device_node *, const char *, struct power_supply **, ssize_t)’ {aka ‘int(struct device_node *, const char *, struct power_supply **, long int)’}
  590 | int power_supply_get_by_phandle_array(struct device_node *np,
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/power/supply/power_supply_core.c:21:
./include/linux/power_supply.h:823:1: note: previous definition of ‘power_supply_get_by_phandle_array’ with type ‘int(struct device_node *, const char *, struct power_supply **, int)’
  823 | power_supply_get_by_phandle_array(struct device_node *np,
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: dea1a925 ("ANDROID: power_supply: Add a helper function to retrieve psy array from phandle")
Fixes: f368f87b ("power: supply: core: convert to fwnnode")
Change-Id: I320dbdfc0d631649087c070489c73fb43ac102d7
Signed-off-by: Tiffany Yang <ynaffit@google.com>