remoteproc: imx_rproc: fix return value check in imx_rproc_addr_init()

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

Fixes: ecadcc47 ("remoteproc: imx_rproc: use devm_ioremap")
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20210312080420.277151-1-weiyongjun1@huawei.comSigned-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

drivers/remoteproc/imx_rproc.c

@@ -464,10 +464,9 @@ static int imx_rproc_addr_init(struct imx_rproc *priv,
 
 		/* Not use resource version, because we might share region */
 		priv->mem[b].cpu_addr = devm_ioremap(&pdev->dev, res.start, resource_size(&res));
-		if (IS_ERR(priv->mem[b].cpu_addr)) {
+		if (!priv->mem[b].cpu_addr) {
 			dev_err(dev, "failed to remap %pr\n", &res);
-			err = PTR_ERR(priv->mem[b].cpu_addr);
-			return err;
+			return -ENOMEM;
 		}
 		priv->mem[b].sys_addr = res.start;
 		priv->mem[b].size = resource_size(&res);