block/dirty-bitmap: fix comment for BlockDirtyBitmap.disabled field

Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20170628120530.31251-10-vsementsov@virtuozzo.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

block/dirty-bitmap.c

@@ -43,7 +43,8 @@ struct BdrvDirtyBitmap {
     BdrvDirtyBitmap *successor; /* Anonymous child; implies frozen status */
     char *name;                 /* Optional non-empty unique ID */
     int64_t size;               /* Size of the bitmap (Number of sectors) */
-    bool disabled;              /* Bitmap is read-only */
+    bool disabled;              /* Bitmap is disabled. It ignores all writes to
+                                   the device */
     int active_iterators;       /* How many iterators are active */
     QLIST_ENTRY(BdrvDirtyBitmap) list;
 };