tools: Move Makefile.arch from perf/config to tools/scripts

After this patch other directories can use this architecture detector
without directly including it from perf's directory. Libbpf would
utilize it to get proper $(ARCH) so it can receive correct uapi include
directory.

Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1452520124-2073-8-git-send-email-wangnan0@huawei.com
[ Add missing srctree definition in tests/make ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@kernel.org>

tools/scripts/Makefile.arch

@@ -0,0 +1,18 @@
+ifndef ARCH
+ARCH := $(shell uname -m 2>/dev/null || echo not)
+endif
+
+ARCH := $(shell echo $(ARCH) | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
+                                  -e s/sun4u/sparc/ -e s/sparc64/sparc/ \
+                                  -e /arm64/!s/arm.*/arm/ -e s/sa110/arm/ \
+                                  -e s/s390x/s390/ -e s/parisc64/parisc/ \
+                                  -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
+                                  -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \
+                                  -e s/tile.*/tile/ )
+
+LP64 := $(shell echo __LP64__ | ${CC} ${CFLAGS} -E -x c - | tail -n 1)
+ifeq ($(LP64), 1)
+  IS_64_BIT := 1
+else
+  IS_64_BIT := 0
+endif