[HELP] SAMD51 Low power mode

### Description

Hi

We are trying to put a board based on the SAMD51 in low power mode.

We configure the register for PM_SLEEPCFG_MODE_STANDBY and use the WFI instruction for entering the lpm.

Interrups are disable by enter_critical_section().

Does someone has some information on the LPM?

BR
Gilberto

### Verification

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