[IA64] remove warning in vmx_final_setup_guest()

This patch removes the warning in vmx_final_setup_guest()
> vmx_init.c:497: warning: unused variable 'sw'

Signed-off-by: Isaku Yamahata <yamahata@xxxxxxxxxxxxx>

diff -r 9dba84bfd55c xen/arch/ia64/vmx/vmx_init.c
--- a/xen/arch/ia64/vmx/vmx_init.c	Fri May 02 17:01:32 2008 +0900
+++ b/xen/arch/ia64/vmx/vmx_init.c	Mon May 12 16:23:53 2008 +0900
@@ -494,7 +494,6 @@
 {
 	vpd_t *vpd;
 	int rc;
-	struct switch_stack *sw;
 
 	vpd = alloc_vpd();
 	ASSERT(vpd);