xen/trace: set up tracepoint skeleton

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
diff --git a/arch/x86/xen/trace.c b/arch/x86/xen/trace.c
new file mode 100644
index 0000000..8cca6164
--- /dev/null
+++ b/arch/x86/xen/trace.c
@@ -0,0 +1,4 @@
+#include <linux/ftrace.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/xen.h>