[Bug 40380] Wine should take dosbox' s configuration instead of creating a new one

https://bugs.winehq.org/show_bug.cgi?id=40380

--- Comment #1 from shankao  ---
There can be an easy way to accomplish this by passing the option -userconf
when launching dosbox. From dosbox's README:

-userconf
        Start DOSBox with the users specific configuration file. Can be used
        together with multiple -conf parameters, but -userconf will always be
        loaded before them.

This option has been added in dosbox 0.74, released more than 6 years ago.

Patch for it:

diff --git a/programs/winevdm/winevdm.c b/programs/winevdm/winevdm.c
index 290ad25..1662008 100644
--- a/programs/winevdm/winevdm.c
+++ b/programs/winevdm/winevdm.c
@@ -195,7 +195,7 @@ static void start_dosbox( const char *appname, const char
*args )
         const char *args[4];
         char *config_file = wine_get_unix_file_name( config );
         args[0] = dosbox;
-        args[1] = "-conf";
+        args[1] = "-userconf -conf";
         args[2] = config_file;
         args[3] = NULL;
         ret = _spawnvp( _P_WAIT, args[0], args );