Handle null mountTimeout in RestoreBackupCommand (#11944)

Author: abh1sar

core/src/main/java/org/apache/cloudstack/backup/RestoreBackupCommand.java

@@ -149,7 +149,7 @@ public void setBackupVolumesUUIDs(List<String> backupVolumesUUIDs) {
     }
 
     public Integer getMountTimeout() {
-        return this.mountTimeout;
+        return this.mountTimeout == null ? 0 : this.mountTimeout;
     }
 
     public void setMountTimeout(Integer mountTimeout) {

plugins/backup/nas/src/main/java/org/apache/cloudstack/backup/NASBackupProvider.java

@@ -405,6 +405,7 @@ public Pair<Boolean, String> restoreBackedUpVolume(Backup backup, Backup.VolumeI
         restoreCommand.setVmExists(null);
         restoreCommand.setVmState(vmNameAndState.second());
         restoreCommand.setRestoreVolumeUUID(backupVolumeInfo.getUuid());
+        restoreCommand.setMountTimeout(NASBackupRestoreMountTimeout.value());
 
         BackupAnswer answer;
         try {