iommu: Fix some W=1 warnings

The code is mostly free of W=1 warning, so fix the following:

drivers/iommu/iommu.c:996: warning: expecting prototype for iommu_group_for_each_dev(). Prototype was for __iommu_group_for_each_dev() instead
drivers/iommu/iommu.c:3048: warning: Function parameter or member 'drvdata' not described in 'iommu_sva_bind_device'
drivers/iommu/ioasid.c:354: warning: Function parameter or member 'ioasid' not described in 'ioasid_get'
drivers/iommu/omap-iommu.c:1098: warning: expecting prototype for omap_iommu_suspend_prepare(). Prototype was for omap_iommu_prepare() instead

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1643366673-26803-1-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

Author: John Garry

drivers/iommu/ioasid.c

@@ -349,6 +349,7 @@ EXPORT_SYMBOL_GPL(ioasid_alloc);
 
 /**
  * ioasid_get - obtain a reference to the IOASID
+ * @ioasid: the ID to get
  */
 void ioasid_get(ioasid_t ioasid)
 {

drivers/iommu/iommu.c

@@ -985,17 +985,6 @@ static int iommu_group_device_count(struct iommu_group *group)
 	return ret;
 }
 
-/**
- * iommu_group_for_each_dev - iterate over each device in the group
- * @group: the group
- * @data: caller opaque data to be passed to callback function
- * @fn: caller supplied callback function
- *
- * This function is called by group users to iterate over group devices.
- * Callers should hold a reference count to the group during callback.
- * The group->mutex is held across callbacks, which will block calls to
- * iommu_group_add/remove_device.
- */
 static int __iommu_group_for_each_dev(struct iommu_group *group, void *data,
 				      int (*fn)(struct device *, void *))
 {
@@ -1010,7 +999,17 @@ static int __iommu_group_for_each_dev(struct iommu_group *group, void *data,
 	return ret;
 }
 
-
+/**
+ * iommu_group_for_each_dev - iterate over each device in the group
+ * @group: the group
+ * @data: caller opaque data to be passed to callback function
+ * @fn: caller supplied callback function
+ *
+ * This function is called by group users to iterate over group devices.
+ * Callers should hold a reference count to the group during callback.
+ * The group->mutex is held across callbacks, which will block calls to
+ * iommu_group_add/remove_device.
+ */
 int iommu_group_for_each_dev(struct iommu_group *group, void *data,
 			     int (*fn)(struct device *, void *))
 {
@@ -3037,6 +3036,7 @@ EXPORT_SYMBOL_GPL(iommu_aux_get_pasid);
  * iommu_sva_bind_device() - Bind a process address space to a device
  * @dev: the device
  * @mm: the mm to bind, caller must hold a reference to it
+ * @drvdata: opaque data pointer to pass to bind callback
  *
  * Create a bond between device and address space, allowing the device to access
  * the mm using the returned PASID. If a bond already exists between @device and

drivers/iommu/omap-iommu.c

@@ -1085,7 +1085,7 @@ static __maybe_unused int omap_iommu_runtime_resume(struct device *dev)
 }
 
 /**
- * omap_iommu_suspend_prepare - prepare() dev_pm_ops implementation
+ * omap_iommu_prepare - prepare() dev_pm_ops implementation
  * @dev:	iommu device
  *
  * This function performs the necessary checks to determine if the IOMMU