power: supply: rt9467: Prevent using uninitialized local variable in rt9467_set_value...

power: supply: rt9467: Prevent using uninitialized local variable in rt9467_set_value_from_ranges()

There is a typo in rt9467_set_value_from_ranges() that can cause leaving local
variable sel with an undefined value which is then used in regmap_field_write().

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 6f7f70e3a8dd ("power: supply: rt9467: Add Richtek RT9467 charger driver")
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Link: https://patch.msgid.link/20251009145308.1830893-1-m.masimov@mt-integration.ru
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>