vim-patch:8.2.2922: computing array length is done in various ways

Problem:    Computing array length is done in various ways.
Solution:   Use ARRAY_LENGTH everywhere. (Ken Takata, closes vim/vim#8305)
eeec254878

src/nvim/memory.c

@@ -573,7 +573,6 @@ void free_all_mem(void)
     return;
   }
   entered_free_all_mem = true;
-
   // Don't want to trigger autocommands from here on.
   block_autocmds();