lib/vsprintf.c: fix bug omitting minus sign of numbers (module_param)

lib/vsprintf.c: Fix bug omitting minus sign of numbers (module_param)

Signed-off-by: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Cc: Yi Yang <yi.y.yang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index fd987b1..6021757 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -234,7 +234,7 @@
 	int ret;							\
 	if (*cp == '-') {						\
 		ret = strict_strtou##type(cp+1, base, res);		\
-		if (ret != 0)						\
+		if (!ret)						\
 			*res = -(*res);					\
 	} else								\
 		ret = strict_strtou##type(cp, base, res);		\