Do not re-define XEN_ROOT in hypervisor sub-Makefiles.

We can globally export it from xen/Makefile instead, as all hypervisor
builds have this Makefile at their root.

Signed-off-by: Keir Fraser <keir@xen.org>

xen/Makefile

@@ -10,6 +10,7 @@ export XEN_WHOAMI	?= $(USER)
 export XEN_DOMAIN	?= $(shell ([ -x /bin/dnsdomainname ] && /bin/dnsdomainname) || ([ -x /bin/domainname ] && /bin/domainname || echo [unknown]))
 
 export BASEDIR := $(CURDIR)
+export XEN_ROOT := $(BASEDIR)/..
 
 .PHONY: default
 default: build

xen/Rules.mk

@@ -11,7 +11,6 @@ crash_debug   ?= n
 frame_pointer ?= n
 lto           ?= n
 
-XEN_ROOT=$(BASEDIR)/..
 include $(XEN_ROOT)/Config.mk
 
 # Hardcoded configuration implications and dependencies.

xen/arch/x86/boot/build32.mk

@@ -1,4 +1,3 @@
-XEN_ROOT=../../../..
 override XEN_TARGET_ARCH=x86_32
 CFLAGS =
 include $(XEN_ROOT)/Config.mk

xen/include/Makefile

@@ -1,4 +1,3 @@
-XEN_ROOT:=$(BASEDIR)/..
 include $(XEN_ROOT)/Config.mk
 
 ifneq ($(CONFIG_COMPAT),)

xen/tools/Makefile

@@ -1,5 +1,4 @@
 
-XEN_ROOT = $(BASEDIR)/..
 include $(XEN_ROOT)/Config.mk
 
 .PHONY: default

xen/tools/figlet/Makefile

@@ -1,5 +1,4 @@
 
-XEN_ROOT = $(BASEDIR)/..
 include $(XEN_ROOT)/Config.mk
 
 figlet: figlet.c