[PATCH v2 5/6] selftests: Generate build output of linux headers to $(OUTPUT)/linux-header-build

[Xiaoyao Li <xiaoyao.li@xxxxxxxxx>]

When build linux headers for selftests with OUTPUT specified, it makes
linux src tree not clean.

Fix it by generating the output file of "headers_install" to a fixed dir
in $(OUTPUT).

Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
---
 tools/testing/selftests/lib.mk | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
index b51ff93da4de..bb830e4817fc 100644
--- a/tools/testing/selftests/lib.mk
+++ b/tools/testing/selftests/lib.mk
@@ -66,6 +66,7 @@ ifeq (1,$(DEFAULT_INSTALL_HDR_PATH))
 	make --no-builtin-rules ARCH=$(ARCH) -C $(top_srcdir) headers_install
 else
 	make --no-builtin-rules INSTALL_HDR_PATH=$(INSTALL_HDR_PATH) \
+		O=$(OUTPUT)/linux-header-build \
 		ARCH=$(ARCH) -C $(top_srcdir) headers_install
 endif
 endif
-- 
2.20.1