os/bluestore: eliminate build warnings

Signed-off-by: Igor Fedotov <[email protected]>

Author: ifed01

src/os/bluestore/BlueStore.cc

@@ -2865,7 +2865,7 @@ uint32_t BlueStore::Blob::merge_blob(CephContext* cct, Blob* blob_to_dissolve)
     auto buf = src->bc.buffer_map.extract(src->bc.buffer_map.cbegin());
     buf.mapped().space = &dst->bc;
     if (dst->bc.buffer_map.count(buf.key()) == 0) {
-      dst->bc.buffer_map.insert({buf.key(), std::move(buf.mapped())});
+      dst->bc.buffer_map.emplace(buf.key(), std::move(buf.mapped()));
     }
   }
   // move BufferSpace writing

src/os/bluestore/BlueStore.h

@@ -1049,7 +1049,7 @@ class BlueStore : public ObjectStore,
 
     void bound_encode_spanning_blobs(size_t& p);
     void encode_spanning_blobs(ceph::buffer::list::contiguous_appender& p);
-    BlobRef get_spanning_blob(int id) {
+    BlobRef& get_spanning_blob(int id) {
       auto p = spanning_blob_map.find(id);
       ceph_assert(p != spanning_blob_map.end());
       return p->second;