iommu: Fix comment for struct iommu_fwspec

Commit 986d5ec ("iommu: Move fwspec->iommu_priv to struct
dev_iommu") removed iommu_priv from fwspec and commit 5702ee2
("ACPI/IORT: Check ATS capability in root complex nodes") added @flags.
Update the struct doc.

Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/20210401154718.307519-2-jean-philippe@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>

include/linux/iommu.h

@@ -571,7 +571,7 @@ struct iommu_group *fsl_mc_device_group(struct device *dev);
  * struct iommu_fwspec - per-device IOMMU instance data
  * @ops: ops for this device's IOMMU
  * @iommu_fwnode: firmware handle for this device's IOMMU
- * @iommu_priv: IOMMU driver private data for this device
+ * @flags: IOMMU_FWSPEC_* flags
  * @num_pasid_bits: number of PASID bits supported by this device
  * @num_ids: number of associated device IDs
  * @ids: IDs which this device may present to the IOMMU