Add an assortment of missing frees and closes.

Coverity's resource-leak checker is on the ball as usual.

unix/gtkdlg.c

@@ -3304,6 +3304,7 @@ int do_config_box(const char *title, Conf *conf, int midsession,
 
     dlg_cleanup(&dp);
     sfree(selparams);
+    ctrl_free_box(ctrlbox);
 
     return dp.retval;
 }

unix/gtkfont.c

@@ -1126,6 +1126,7 @@ static void x11font_enum_fonts(GtkWidget *widget,
 	}
     }
     XFreeFontNames(fontnames);
+    sfree(tmp);
 }
 
 static char *x11font_canonify_fontname(GtkWidget *widget, const char *name,

unix/uxpgnt.c

@@ -978,6 +978,8 @@ void run_agent(void)
         fprintf(stderr, "pageant: %s: %s\n", socketname, strerror(errno));
         exit(1);
     }
+
+    conf_free(conf);
 }
 
 int main(int argc, char **argv)