Fix some compilation warnings

src/blockstore/blockstore_flush.h

@@ -58,7 +58,6 @@ class journal_flusher_co
     int i, res;
     bool read_to_fill_incomplete;
     int copy_count;
-    bool do_repeat = false;
 
     friend class journal_flusher_t;
 

src/blockstore/blockstore_heap.h

@@ -163,7 +163,7 @@ using heap_mvcc_map_t = robin_hood::unordered_flat_map<object_id, heap_object_mv
 
 class blockstore_heap_t
 {
-    friend class heap_entry_t;
+    friend struct heap_entry_t;
 
     blockstore_disk_t *dsk = NULL;
     uint8_t* buffer_area = NULL;

src/blockstore/blockstore_init.cpp

@@ -269,7 +269,7 @@ resume_6:
         }
         GET_SQE();
         data->iov = (iovec){ buf, len };
-        data->callback = [this, offset, cb](ring_data_t *data)
+        data->callback = [offset, cb](ring_data_t *data)
         {
             if (data->res < 0)
             {