lib: Add self-test for atomic64_t

This patch adds self-test on boot code for atomic64_t.

This has been used to test the later changes in this patchset.

Signed-off-by: Luca Barbieri <luca@luca-barbieri.com>
LKML-Reference: <1267005265-27958-4-git-send-email-luca@luca-barbieri.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/lib/Makefile b/lib/Makefile
index 347ad8d..4af4786 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -99,6 +99,8 @@
 
 obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o
 
+obj-$(CONFIG_ATOMIC64_SELFTEST) += atomic64_test.o
+
 hostprogs-y	:= gen_crc32table
 clean-files	:= crc32table.h