media: imx-jpeg: Fix return value check in mxc_jpeg_attach_pm_domains()

In case of error, the function device_link_add() returns NULL
pointer not ERR_PTR(). The IS_ERR() test in the return value
check should be replaced with NULL test.

Fixes: 2db16c6e ("media: imx-jpeg: Add V4L2 driver for i.MX8 JPEG Encoder/Decoder")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/imx-jpeg/mxc-jpeg.c

@@ -1943,8 +1943,8 @@ static int mxc_jpeg_attach_pm_domains(struct mxc_jpeg_dev *jpeg)
 						   DL_FLAG_STATELESS |
 						   DL_FLAG_PM_RUNTIME |
 						   DL_FLAG_RPM_ACTIVE);
-		if (IS_ERR(jpeg->pd_link[i])) {
-			ret = PTR_ERR(jpeg->pd_link[i]);
+		if (!jpeg->pd_link[i]) {
+			ret = -EINVAL;
 			goto fail;
 		}
 	}