blockjob: Update function name in comments

Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Message-id: 1428069921-2957-5-git-send-email-famz@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

block/backup.c

@@ -287,7 +287,7 @@ static void coroutine_fn backup_run(void *opaque)
                 break;
             }
 
-            /* we need to yield so that qemu_aio_flush() returns.
+            /* we need to yield so that bdrv_drain_all() returns.
              * (without, VM does not reboot)
              */
             if (job->common.speed) {

block/mirror.c

@@ -475,7 +475,7 @@ static void coroutine_fn mirror_run(void *opaque)
                         (cnt + s->sectors_in_flight) * BDRV_SECTOR_SIZE;
 
         /* Note that even when no rate limit is applied we need to yield
-         * periodically with no pending I/O so that qemu_aio_flush() returns.
+         * periodically with no pending I/O so that bdrv_drain_all() returns.
          * We do so every SLICE_TIME nanoseconds, or when there is an error,
          * or when the source is clean, whichever comes first.
          */