SDL: hidapi: Avoid memcpy'ing to NULL.

SDL Commits
1 
From c6d9fb1ad71462bc844c6ca41e2ac7fe7cec3883 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Mon, 6 Nov 2023 13:48:07 -0500
Subject: [PATCH] hidapi: Avoid memcpy'ing to NULL.

(This fix was originally from @themightyoarfish on GitHub. Thanks!)

Fixes #8428.
Reference PR #8431.
---
 src/hidapi/mac/hid.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/hidapi/mac/hid.c b/src/hidapi/mac/hid.c
index 20c664501d5e..1eb49b5d3120 100644
--- a/src/hidapi/mac/hid.c
+++ b/src/hidapi/mac/hid.c
@@ -1230,7 +1230,9 @@ static int return_data(hid_device *dev, unsigned char *data, size_t length)
 	   return buffer (data), and delete the liked list item. */
 	struct input_report *rpt = dev->input_reports;
 	size_t len = (length < rpt->len)? length: rpt->len;
-	memcpy(data, rpt->data, len);
+	if (data != NULL) {
+		memcpy(data, rpt->data, len);
+	}
 	dev->input_reports = rpt->next;
 	free(rpt->data);
 	free(rpt);