soc: nordic: nrf53: Remove broken PM_S2RAM support

Remove dead code that cannot be enabled.

Kconfig prevents us from enabling PM_S2RAM on 53 because it is not
supported any more.

But we still have some dead code left over in soc.c, so we delete this
code.

Signed-off-by: Sebastian Bøe <sebastian.boe@nordicsemi.no>
1 file changed