tree-wide: apply equals-null.cocci

Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/combine-diff.c b/combine-diff.c
index d93782d..b724f02 100644
--- a/combine-diff.c
+++ b/combine-diff.c
@@ -195,10 +195,10 @@ static struct lline *coalesce_lines(struct lline *base, int *lenbase,
 	struct lline *baseend, *newend = NULL;
 	int i, j, origbaselen = *lenbase;
 
-	if (newline == NULL)
+	if (!newline)
 		return base;
 
-	if (base == NULL) {
+	if (!base) {
 		*lenbase = lennew;
 		return newline;
 	}