drm/nouveau/disp: switch to use kmemdup() helper

Use kmemdup() helper instead of open-coding to
simplify the code.

Signed-off-by: Chen Haonan <chen.haonan2@zte.com.cn>
Reviewed-by: Yang Guang <yang.guang5@zte.com.cn>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/202401091424115185126@zte.com.cn

drivers/gpu/drm/nouveau/nvif/outp.c

@@ -452,13 +452,12 @@ nvif_outp_edid_get(struct nvif_outp *outp, u8 **pedid)
 	if (ret)
 		goto done;
 
-	*pedid = kmalloc(args->size, GFP_KERNEL);
+	*pedid = kmemdup(args->data, args->size, GFP_KERNEL);
 	if (!*pedid) {
 		ret = -ENOMEM;
 		goto done;
 	}
 
-	memcpy(*pedid, args->data, args->size);
 	ret = args->size;
 done:
 	kfree(args);