[PATCH] string: Replace = with += in CFLAGS-tst-xbzero-opt.c

[H.J. Lu]

Replace = with += in CFLAGS-tst-xbzero-opt.c to allow sysdeps Makefile
to define CFLAGS-tst-xbzero-opt.c.

Any comments?

H.J.
	* string/Makefile (CFLAGS-tst-xbzero-opt.c): Replace = with +=.
---
 string/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/string/Makefile b/string/Makefile
index d7e90a38a5..618b737b13 100644
--- a/string/Makefile
+++ b/string/Makefile
@@ -75,7 +75,7 @@ CFLAGS-tst-strlen.c = -fno-builtin
 CFLAGS-stratcliff.c = -fno-builtin
 CFLAGS-test-ffs.c = -fno-builtin
 CFLAGS-tst-inlcall.c = -fno-builtin
-CFLAGS-tst-xbzero-opt.c = -O3
+CFLAGS-tst-xbzero-opt.c += -O3
 # BZ 21006: Resolve all functions but at least explicit_bzero at startup.
 # Otherwise the test fails on s390x as the memcpy in prepare_test_buffer is
 # done by loading r4 / r5 with the test_pattern and using store multiple
-- 
2.14.3