[rstmgr, sival] Fix alert_info test on ROM_EXT + FPGA

The test generates a kTopEarlgreyAlertIdFlashCtrlFatalErr
alert only on the FPGA and with ROM_EXT. It doesn't happens on
Silicon probrably because it has the seeds.

sw/device/tests/rstmgr_alert_info_test.c

@@ -701,6 +701,12 @@ static void init_expected_cause(void) {
       .alert_info.alert_cause[kTopEarlgreyAlertIdI2c0FatalFault] = 1;
   kExpectedInfo[kRound3]
       .alert_info.alert_cause[kTopEarlgreyAlertIdSpiHost0FatalFault] = 1;
+
+  if (kBootStage == kBootStageOwner &&
+      (kDeviceType == kDeviceFpgaCw310 || kDeviceType == kDeviceFpgaCw340)) {
+    kExpectedInfo[kRound3]
+        .alert_info.alert_cause[kTopEarlgreyAlertIdFlashCtrlFatalErr] = 1;
+  }
 }
 bool test_main(void) {
   uint32_t event_idx = 0;