Define CLEAN macro to allow Makefiles to override common clean target
in lib.mk. This will help fix the following failures:

warning: overriding recipe for target 'clean'
../lib.mk:55: warning: ignoring old recipe for target 'clean'

Signed-off-by: Shuah Khan <redacted>
---
 tools/testing/selftests/lib.mk | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
index 775c589..959273c 100644
--- a/tools/testing/selftests/lib.mk
+++ b/tools/testing/selftests/lib.mk

@@ -51,8 +51,12 @@ endef
 emit_tests:
 	$(EMIT_TESTS)
 
-clean:
+define CLEAN
 	$(RM) -r $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES) $(EXTRA_CLEAN)
+endef
+
+clean:
+	$(CLEAN)
 
 $(OUTPUT)/%:%.c
 	$(LINK.c) $^ $(LDLIBS) -o $@

-- 
2.9.3