xen: clean up domain mode predicates

There are four operating modes Xen code may find itself running in:
 - native
 - hvm domain
 - pv dom0
 - pv domU

Clean up predicates for testing for these states to make them more consistent.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/drivers/input/xen-kbdfront.c b/drivers/input/xen-kbdfront.c
index 9ce3b3b..3ab6362 100644
--- a/drivers/input/xen-kbdfront.c
+++ b/drivers/input/xen-kbdfront.c
@@ -335,11 +335,11 @@
 
 static int __init xenkbd_init(void)
 {
-	if (!is_running_on_xen())
+	if (!xen_domain())
 		return -ENODEV;
 
 	/* Nothing to do if running in dom0. */
-	if (is_initial_xendomain())
+	if (xen_initial_domain())
 		return -ENODEV;
 
 	return xenbus_register_frontend(&xenkbd);