suit: Always validate signatures for nordic envelopes

This PR disables The validation skip of SDFW, Nordic Top
System Controller manifests based on LCS.

This way the signature of these manifests is always checked.

Signed-off-by: Artur Hadasz <[email protected]>

Author: ahasztag

subsys/suit/mci/src/suit_mci_nrf54h20.c

@@ -188,16 +188,7 @@ static bool skip_validation(suit_manifest_role_t role)
 	case SUIT_MANIFEST_SEC_TOP:
 	case SUIT_MANIFEST_SEC_SDFW:
 	case SUIT_MANIFEST_SEC_SYSCTRL:
-		current_lcs = lcs_get(LCS_DOMAIN_ID_SECURE);
-
-		/* TODO:
-		 * NCSDK-26255
-		 * Once keys are provisioned, validation skip for Secure domain should be disabled.
-		 * return false;
-		 */
-
-		LOG_WRN("SUIT: Validation skip is enabled for Secure domain.");
-		break;
+		return false;
 
 	case SUIT_MANIFEST_APP_ROOT:
 	case SUIT_MANIFEST_APP_RECOVERY: