Fix segfaults seen on IBM ThinkPad T23 when changing TV signal format.
Thanks to the upstream author, Tim Roberts, for help in creating this patch.

--- s3switch.c.orig	2002-09-12 01:25:33.000000000 +0300
+++ s3switch.c	2004-07-22 13:28:32.000000000 +0300
@@ -100,4 +100,8 @@
     ioperm( 0x40, 4, enable );
+    ioperm( 0x4f, 1, enable );
     ioperm( 0x61, 1, enable );
+    ioperm( 0x70, 1, enable );
+    ioperm( 0x71, 1, enable );
     ioperm( 0x80, 1, enable );
+    ioperm( 0xb2, 1, enable );
     ioperm( 0x3b0, 0x30, enable );