block/rbd: remove processed options from qdict

Commit 4bfb274 added some QAPIfication of option parsing in
qemu_rbd_open().  We need to remove all the options we processed,
otherwise in bdrv_open_inherit() we will think the remaining options are
invalid.

(This needs to go in 2.12 to avoid a regression that prevents rbd
from being opened.)

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/block/rbd.c b/block/rbd.c
index 5b64849..c9359d0 100644
--- a/block/rbd.c
+++ b/block/rbd.c
@@ -623,6 +623,7 @@
     BlockdevOptionsRbd *opts = NULL;
     Visitor *v;
     QObject *crumpled = NULL;
+    const QDictEntry *e;
     Error *local_err = NULL;
     const char *filename;
     char *keypairs, *secretid;
@@ -671,6 +672,12 @@
         goto out;
     }
 
+    /* Remove the processed options from the QDict (the visitor processes
+     * _all_ options in the QDict) */
+    while ((e = qdict_first(options))) {
+        qdict_del(options, e->key);
+    }
+
     r = qemu_rbd_connect(&s->cluster, &s->io_ctx, opts,
                          !(flags & BDRV_O_NOCACHE), keypairs, secretid, errp);
     if (r < 0) {