log_init: call log_path_init (#11501)

This has to be done after `init_homedir` for XDG default and `set_init_1` for
lookup from env, which could be done earlier likely (to help with
https://github.com/neovim/neovim/issues/10937), but this keeps it in
sync with Vim.

Fixes https://github.com/neovim/neovim/issues/11499.

src/nvim/log.c

@@ -93,6 +93,7 @@ static bool log_path_init(void)
 void log_init(void)
 {
   uv_mutex_init(&mutex);
+  log_path_init();
 }
 
 void log_lock(void)