xen: Attempt to patch inline versions of common operations

This patchs adds the mechanism to allow us to patch inline versions of
common operations.

The implementations of the direct-access versions save_fl, restore_fl,
irq_enable and irq_disable are now in assembler, and the same code is
used for both out of line and inline uses.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Keir Fraser <keir@xensource.com>
diff --git a/arch/i386/xen/Makefile b/arch/i386/xen/Makefile
index 7bf2ce3..343df24 100644
--- a/arch/i386/xen/Makefile
+++ b/arch/i386/xen/Makefile
@@ -1,4 +1,4 @@
 obj-y		:= enlighten.o setup.o features.o multicalls.o mmu.o \
-			events.o time.o manage.o
+			events.o time.o manage.o xen-asm.o
 
 obj-$(CONFIG_SMP)	+= smp.o