LUA: (really) fix infinite loop

modules/misc/lua/intf.c

@@ -83,15 +83,17 @@ static const struct
 
 static const char *WordInList( const char *psz_list, const char *psz_word )
 {
-    size_t i_len = strlen( psz_word );
-
-    for( const char *s = psz_list; s; s = strchr( s, ',' ) )
+    for( ;; )
     {
-        if( !strncmp( s, psz_word, i_len )
-         && memchr( ",", s[i_len], 2 ) )
-            return s;
+        const char *end = strchr( psz_list, ',' );
+        if( end == NULL )
+            break;
+
+        if( !strncmp( psz_list, psz_word, end - psz_list ) )
+            return psz_list;
+        psz_list = end + 1;
     }
-    return NULL;
+    return strcmp( psz_list, psz_word ) ? psz_list : NULL;
 }
 
 static char *GetModuleName( intf_thread_t *p_intf )