fix prompt color style how it used to be

This is the style how it was before the big Xft change. The colors were
inverted, this was not the case before the change.

Reported by "zvz" on #suckless IRC, thanks!

dmenu.c

@@ -207,7 +207,7 @@ drawmenu(void) {
 
 	if(prompt && *prompt) {
 		drw_setscheme(drw, &scheme[SchemeSel]);
-		drw_text(drw, x, 0, promptw, bh, prompt, 1);
+		drw_text(drw, x, 0, promptw, bh, prompt, 0);
 		x += promptw;
 	}
 	/* draw input field */