storage_util: Remove unnecessary check

Commit id 'a48c7141' altered the logic a bit and didn't
remove an unnecessary check as info.encryption is true when
vol->target.encryption != NULL, so if we enter the if segment
with info.format == VIR_STORAGE_FILE_RAW && vol->target.encryption
!= NULL, then there's no way info.encryption could be false.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

src/storage/storage_util.c

@@ -1175,11 +1175,6 @@ virStorageBackendCreateQemuImgCmdFromVol(virStoragePoolObjPtr pool,
                            _("cannot use inputvol with encrypted raw volume"));
             return NULL;
         }
-        if (!info.encryption) {
-            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
-                           _("missing encryption description"));
-            return NULL;
-        }
         if (vol->target.encryption->format == VIR_STORAGE_ENCRYPTION_FORMAT_LUKS) {
             type = "luks";
         } else {