sheepdog: qemu_bh_new() can't return null pointer, drop check

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>

block/sheepdog.c

@@ -449,13 +449,7 @@ static int sd_schedule_bh(QEMUBHFunc *cb, SheepdogAIOCB *acb)
     }
 
     acb->bh = qemu_bh_new(cb, acb);
-    if (!acb->bh) {
-        error_report("oom: %d %d\n", acb->aiocb_type, acb->aiocb_type);
-        return -EIO;
-    }
-
     qemu_bh_schedule(acb->bh);
-
     return 0;
 }