[PATCH] selftests/clone3: Add gun99 to compile in Makefile.

[Xingxing Su <suxingxing@xxxxxxxxxxx>]

CFLAGS add -std=gnu99.

Fllowing build error:

test_core.c: In function ‘test_cgcore_destroy’:
test_core.c:87:2: error: ‘for’ loop initial declarations are only
allowed in C99 mode
  for (int i = 0; i < 10; i++) {
  ^
test_core.c:87:2: note: use option -std=c99 or -std=gnu99 to compile
your code

Signed-off-by: Xingxing Su <suxingxing@xxxxxxxxxxx>
---
 tools/testing/selftests/clone3/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/clone3/Makefile b/tools/testing/selftests/clone3/Makefile
index ef7564c..88354a8 100644
--- a/tools/testing/selftests/clone3/Makefile
+++ b/tools/testing/selftests/clone3/Makefile
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
-CFLAGS += -g -I../../../../usr/include/
+CFLAGS += -g -std=gnu99 -I../../../../usr/include/ 
 LDLIBS += -lcap
 
 TEST_GEN_PROGS := clone3 clone3_clear_sighand clone3_set_tid \
-- 
1.8.3.1