patch 9.1.0341: Problem: a few memory leaks are found

Problem:  a few memory leaks are found
          (LuMingYinDetect )
Solution: properly free the memory

Fixes the following problems:
- Memory leak in f_maplist()
  fixes: #14486

- Memory leak in option.c
  fixes: #14485

- Memory leak in f_resolve()
  fixes: #14484

- Memory leak in f_autocmd_get()
  related: #14474

- Memory leak in dict_extend_func()
  fixes: #14477
  fixes: #14238

closes: #14517

Signed-off-by: Christian Brabandt <cb@256bit.org>

src/option.c

@@ -853,7 +853,10 @@ set_string_default_esc(char *name, char_u *val, int escape)
 
     opt_idx = findoption((char_u *)name);
     if (opt_idx < 0)
+    {
+	vim_free(p);
 	return;
+    }
 
     if (options[opt_idx].flags & P_DEF_ALLOCED)
 	vim_free(options[opt_idx].def_val[VI_DEFAULT]);