[nrf noup] dts: choose a crypto accelerator for entropy

Set PSA as the entropy source for nRF54lm20a target.
PSA is the only NCS-supported interface to CRACEN.

Signed-off-by: Piotr Pryga <[email protected]>

Author: ppryga-nordic

dts/arm/nordic/nrf54lm20a_enga_cpuapp.dtsi

@@ -18,7 +18,7 @@ nvic: &cpuapp_nvic {};
 / {
 	chosen {
 		zephyr,bt-hci = &bt_hci_sdc;
-		zephyr,entropy = &rng;
+		zephyr,entropy = &psa_rng;
 	};
 
 	soc {
@@ -29,7 +29,7 @@ nvic: &cpuapp_nvic {};
 
 	psa_rng: psa-rng {
 		compatible = "zephyr,psa-crypto-rng";
-		status = "disabled";
+		status = "okay";
 	};
 
 	rng: rng {