Add missing return in replaceVolumeWithBackup

Author: abh1sar

plugins/hypervisors/kvm/src/main/java/com/cloud/hypervisor/kvm/resource/wrapper/LibvirtRestoreBackupCommandWrapper.java

@@ -289,6 +289,7 @@ private boolean replaceVolumeWithBackup(KVMStoragePoolManager storagePoolMgr, Pr
         if (hasBackingChain(backupPath)) {
             String[] qemuImgCmd = new String[] { Script.getExecutableAbsolutePath("qemu-img"), "convert", "-O", "qcow2", backupPath, volumePath };
             int flattenExit = Script.executeCommandForExitValue(qemuImgCmd);
+            return flattenExit == 0;
         }
 
         String[] rsyncCmd = new String[] { Script.getExecutableAbsolutePath("rsync"), "-az", backupPath, volumePath };