enable Xen support by default.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
diff --git a/src/Kconfig b/src/Kconfig
index 25b2b1b..8120ff7 100644
--- a/src/Kconfig
+++ b/src/Kconfig
@@ -13,7 +13,7 @@
     config XEN
         depends on !COREBOOT
         bool "Build for Xen HVM"
-        default n
+        default y
         help
             Configure to be used by xen hvmloader, for a HVM guest.