soc: arm: stm32[l4|wb]: fix power state exit

When we wake-up of deep sleep power state, we want to disable it.
Otherwise, when the cpu will go next to idle mode during a
SYS_POWER_STATE_ACTIVE, it will go into deep sleep mode
instead of a sleep mode.

fixes: #26896

Signed-off-by: Julien D'Ascenzio <julien.dascenzio@paratronic.fr>