Do not complain on empty first block

src/kv_db.cpp

@@ -233,6 +233,7 @@ int kv_block_t::parse(uint64_t offset, uint8_t *data, int size)
     if (blk->magic == 0 || blk->type == KV_EMPTY)
     {
         // empty block
+        if (offset != 0)
             fprintf(stderr, "K/V: Block %lu is %s\n", offset, blk->magic == 0 ? "empty" : "cleared");
         return -ENOTBLK;
     }