os/bluestore: remove wrong assert

Signed-off-by: Pere Diaz Bou <pere-altea@hotmail.com>

Author: pereman2

src/os/bluestore/BlueStore.cc

@@ -1328,7 +1328,6 @@ struct TwoQBufferCacheShard : public BlueStore::BufferCacheShard {
     dout(20) << __func__ << " level " << level << " near " << near
              << " on " << *b
              << " which has cache_private " << b->cache_private << dendl;
-    ceph_assert(ceph_mutex_is_locked(cache));  // see _txc_finish_io
     ceph_assert(b->is_clean() || b->is_empty());
     if (near) {
       b->cache_private = near->cache_private;