Merge pull request #194 in YUNIONIO/onecloud from ~QUXUAN/onecloud:bugfix/qx-storage-choise to release/2.0.0

* commit 'f3b4b4d3146c9ac5b12bad89eb3d48842984aab0':
  避免只使用第一个storage

pkg/compute/models/hosts.go

@@ -529,7 +529,8 @@ func (self *SHost) GetAttachedStorageCapacity() SStorageCapacity {
 func _getLeastUsedStorage(storages []SStorage, backends []string) *SStorage {
 	var best *SStorage
 	var bestCap int
-	for _, s := range storages {
+	for i := 0; i < len(storages); i++ {
+		s := storages[i]
 		if len(backends) > 0 {
 			in, _ := utils.InStringArray(s.StorageType, backends)
 			if !in {