block: Release allocated options after bdrv_open

They aren't used afterwards nor supposed to be stored by a bdrv_create
handler.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/block.c b/block.c
index f463ec4..48305b7 100644
--- a/block.c
+++ b/block.c
@@ -540,6 +540,7 @@
         }
 
         ret = bdrv_create(bdrv_qcow2, tmp_filename, options);
+        free_option_parameters(options);
         if (ret < 0) {
             return ret;
         }