status: fix null termination with "-b"

When the "-z" option is given to status, we are supposed to
NUL-terminate each record. However, the "-b" code to show
the tracking branch did not respect this, and always ended
with a newline.
Signed-off-by: NJeff King <peff@peff.net>

t/t7508-status.sh

@@ -271,6 +271,15 @@ test_expect_success 'status -s -b' '
 
 '
 
+test_expect_success 'status -s -z -b' '
+	tr "\\n" Q <expect >expect.q &&
+	mv expect.q expect &&
+	git status -s -z -b >output &&
+	nul_to_q <output >output.q &&
+	mv output.q output &&
+	test_cmp expect output
+'
+
 test_expect_success 'setup dir3' '
 	mkdir dir3 &&
 	: >dir3/untracked1 &&

wt-status.c

@@ -889,8 +889,8 @@ static void wt_shortstatus_print_tracking(struct wt_status *s)
 	if (s->is_initial)
 		color_fprintf(s->fp, header_color, _("Initial commit on "));
 	if (!stat_tracking_info(branch, &num_ours, &num_theirs)) {
-		color_fprintf_ln(s->fp, branch_color_local,
-			"%s", branch_name);
+		color_fprintf(s->fp, branch_color_local, "%s", branch_name);
+		fputc(s->null_termination ? '\0' : '\n', s->fp);
 		return;
 	}
 
@@ -914,7 +914,8 @@ static void wt_shortstatus_print_tracking(struct wt_status *s)
 		color_fprintf(s->fp, branch_color_remote, "%d", num_theirs);
 	}
 
-	color_fprintf_ln(s->fp, header_color, "]");
+	color_fprintf(s->fp, header_color, "]");
+	fputc(s->null_termination ? '\0' : '\n', s->fp);
 }
 
 void wt_shortstatus_print(struct wt_status *s, int show_branch)