winmm: remove misleading message

[Dan Kegel]

Jeff wrote:
> Remove a message suggesting that Wine should be pointed at a windows installation.
>
> -	    FIXME("Couldn't load driver for type %s.\n"
> -		  "If you don't have a windows installation accessible from Wine,\n"
> -		  "you perhaps forgot to create a [mci] section in system.ini\n",
> +	    FIXME("Couldn't load driver for type %s.\n",

The [mci] section in system.ini advice is still valid and usful, I think.
You probably just want to remove the middle line.
- Dan