Input: pm8941-pwrkey - add support for PON GEN3 base addresses

Input: pm8941-pwrkey - add support for PON GEN3 base addresses

Currently, PON address is read from the "reg" property. For PON GEN3,
which starts with PMK8350, the "reg" property will have both the PON
HLOS and PON PBS addesses defined. Add support so that all PON
generations can be configured.

Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Anjelique Melendez <quic_amelende@quicinc.com>
Link: https://lore.kernel.org/r/20220422191239.6271-4-quic_amelende@quicinc.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>