dmaengine: idxd: Fix missing error code in idxd_cdev_open()

The error code is missing in this code scenario, add the error code
'-EINVAL' to the return value 'rc'.

Eliminate the follow smatch warning:

drivers/dma/idxd/cdev.c:113 idxd_cdev_open() warn: missing error code
'rc'.
Reported-by: NAbaci Robot <abaci@linux.alibaba.com>
Signed-off-by: NJiapeng Chong <jiapeng.chong@linux.alibaba.com>
Acked-by: NDave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/1622628446-87909-1-git-send-email-jiapeng.chong@linux.alibaba.comSigned-off-by: NVinod Koul <vkoul@kernel.org>

drivers/dma/idxd/cdev.c

@@ -110,6 +110,7 @@ static int idxd_cdev_open(struct inode *inode, struct file *filp)
 		pasid = iommu_sva_get_pasid(sva);
 		if (pasid == IOMMU_PASID_INVALID) {
 			iommu_sva_unbind_device(sva);
+			rc = -EINVAL;
 			goto failed;
 		}