[PATCH] perf: fix building error in x86_64 when dwarf unwind is on

[Wang Nan <wangnan0@huawei.com>]

When build with 'make ARCH=x86' and dwarf unwind is on, there is a
compiling error:

   CC       /home/wn/perf/arch/x86/util/unwind-libdw.o
   CC       /home/wn/perf/arch/x86/tests/regs_load.o
 arch/x86/tests/regs_load.S: Assembler messages:
 arch/x86/tests/regs_load.S:65: Error: operand type mismatch for `push'
 arch/x86/tests/regs_load.S:72: Error: operand type mismatch for `pop'
 make[1]: *** [/home/wn/perf/arch/x86/tests/regs_load.o] Error 1
 make[1]: INTERNAL: Exiting with 25 jobserver tokens available; should be 24!
 make: *** [all] Error 2
 ...

Which is caused by incorrectly undefine macro HAVE_ARCH_X86_64_SUPPORT.
'config/Makefile.arch' tests __x86_64__ only when 'ARCH=x86_64'. However,
with 'ARCH=x86', the underlying compile may also be x86_64, which causes
mismatching.

This patch fixes it by checking __x86_64__ in both case of
'ARCH=x86_64' and 'ARCH=x86'.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
---
 tools/perf/config/Makefile.arch | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/perf/config/Makefile.arch b/tools/perf/config/Makefile.arch
index 851cd01..303a096 100644
--- a/tools/perf/config/Makefile.arch
+++ b/tools/perf/config/Makefile.arch
@@ -15,6 +15,8 @@ endif
 
 ifeq ($(ARCH),x86_64)
   override ARCH := x86
+endif
+ifeq ($(ARCH),x86)
   IS_X86_64 := 0
   ifeq (, $(findstring m32,$(CFLAGS)))
     IS_X86_64 := $(shell echo __x86_64__ | ${CC} -E -x c - | tail -n 1)
-- 
1.8.4