regulator: Add property for WDOG_B warm reset

Make it possible to do warm reset on WDOG_B assertion.

Signed-off-by: Rickard x Andersson <rickaran@axis.com>
Link: https://lore.kernel.org/r/20220429072211.24957-3-rickaran@axis.com
Signed-off-by: Mark Brown <broonie@kernel.org>