Always use ARCH_DIR

The top-level makefile defines an ARCH_DIR variable. Always use
it rather than referencing ARCH directly, since ARCH may be set
by the user on the command line and that raw input may not be
what needs to be used internally.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Makefile

@@ -101,8 +101,8 @@ else
 endif
 
 CFLAGS		+= $(WARNINGS) $(DEFINES)
-SYSCALL-LIB	:= arch/$(ARCH)/syscalls.built-in.o
-ARCH-LIB	:= arch/$(ARCH)/crtools.built-in.o
+SYSCALL-LIB	:= $(ARCH_DIR)/syscalls.built-in.o
+ARCH-LIB	:= $(ARCH_DIR)/crtools.built-in.o
 CRIU-SO		:= libcriu
 CRIU-LIB	:= lib/$(CRIU-SO).so
 CRIU-INC	:= lib/criu.h include/criu-plugin.h include/criu-log.h protobuf/rpc.proto
@@ -126,7 +126,7 @@ build-crtools := -r -R -f scripts/Makefile.build makefile=Makefile.crtools obj
 PROGRAM		:= criu
 
 .PHONY: all zdtm test rebuild clean distclean tags cscope	\
-	docs help pie protobuf arch/$(ARCH) clean-built lib
+	docs help pie protobuf $(ARCH_DIR) clean-built lib
 
 ifeq ($(GCOV),1)
 %.o $(PROGRAM): override CFLAGS += --coverage
@@ -140,14 +140,14 @@ protobuf/%::
 protobuf:
 	$(Q) $(MAKE) $(build)=protobuf all
 
-arch/$(ARCH)/%:: protobuf
-	$(Q) $(MAKE) $(build)=arch/$(ARCH) $@
-arch/$(ARCH): protobuf
-	$(Q) $(MAKE) $(build)=arch/$(ARCH) all
+$(ARCH_DIR)/%:: protobuf
+	$(Q) $(MAKE) $(build)=$(ARCH_DIR) $@
+$(ARCH_DIR): protobuf
+	$(Q) $(MAKE) $(build)=$(ARCH_DIR) all
 
-pie/%:: arch/$(ARCH)
+pie/%:: $(ARCH_DIR)
 	$(Q) $(MAKE) $(build)=pie $@
-pie: arch/$(ARCH)
+pie: $(ARCH_DIR)
 	$(Q) $(MAKE) $(build)=pie all
 
 %.o %.i %.s %.d: $(VERSION_HEADER) pie
@@ -181,7 +181,7 @@ test: zdtm
 
 clean-built:
 	$(Q) $(RM) $(VERSION_HEADER)
-	$(Q) $(MAKE) $(build)=arch/$(ARCH) clean
+	$(Q) $(MAKE) $(build)=$(ARCH_DIR) clean
 	$(Q) $(MAKE) $(build)=protobuf clean
 	$(Q) $(MAKE) $(build)=pie clean
 	$(Q) $(MAKE) $(build)=lib clean

Makefile.crtools

@@ -57,7 +57,7 @@ obj-y	+= kerndat.o
 obj-y	+= stats.o
 obj-y	+= string.o
 obj-y	+= sigframe.o
-obj-y	+= arch/$(ARCH)/vdso.o
+obj-y	+= $(ARCH_DIR)/vdso.o
 obj-y	+= cr-service.o
 obj-y	+= sd-daemon.o
 obj-y	+= plugin.o

lib/Makefile

@@ -2,7 +2,7 @@ lib-so			+= $(CRIU-SO)
 obj-y			+= criu.o
 obj-ext-src-y		+= protobuf/rpc.pb-c.o
 
-includes		+= -iquote $(obj)/../arch/$(ARCH)/include -iquote $(obj)/../include -iquote $(obj)/.. -iquote $(obj)/../protobuf
+includes		+= -iquote $(obj)/../$(ARCH_DIR)/include -iquote $(obj)/../include -iquote $(obj)/.. -iquote $(obj)/../protobuf
 cflags-y		+= $(includes) -fPIC -Wa,--noexecstack -fno-stack-protector
 cflags-so		+= $(CFLAGS) -rdynamic -Wl,-soname,$(lib-so).so.$(VERSION_SO_MAJOR)
 ldflags-so		+= -lprotobuf-c