[PATCH xserver] tests: fix library order comment

[Mihail Konev]

ld.gold ignores --as-needed
(Observable by: make -C test tests V=1 CFLAGS='-v')

Fixes: b1a69863 ("tests: shuffle around the linking order")
Signed-off-by: Mihail Konev <k.mvc at ya.ru>
---
Ubuntu patches gcc builtin -specs= file (the gcc -dumpspec),
but gold ignores the arg.

 test/Makefile.am | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/Makefile.am b/test/Makefile.am
index e7fe587bb858..1cf03c472bc4 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -225,8 +225,8 @@ endif
 
 endif !XORG
 
-# GNU LD scans only in one direction, add the following dependencies at the end
-# so as they get picked up by the previously-linked libraries
+# Shared libraries must be added at the end to not be discarded by
+#  gcc -Wl,--as-needed ...
 tests_LDADD += $(XORG_SYS_LIBS) $(XSERVER_SYS_LIBS) $(GLX_SYS_LIBS)
 
 endif ENABLE_UNIT_TESTS
-- 
2.9.2