iommufd: Fix iommu_vevent_header tables markup

Stephen Rothwell reports htmldocs warnings on iommufd_vevent_header
tables:

Documentation/userspace-api/iommufd:323: ./include/uapi/linux/iommufd.h:1048: CRITICAL: Unexpected section title or transition.

------------------------------------------------------------------------- [docutils]
WARNING: kernel-doc './scripts/kernel-doc -rst -enable-lineno -sphinx-version 8.1.3 ./include/uapi/linux/iommufd.h' processing failed with: Documentation/userspace-api/iommufd:323: ./include/uapi/linux/iommufd.h:1048: (SEVERE/4) Unexpected section title or transition.

-------------------------------------------------------------------------

These are because Sphinx confuses the tables for section headings. Fix
the table markup to squash away above warnings.

Fixes: e36ba5a ("iommufd: Add IOMMUFD_OBJ_VEVENTQ and IOMMUFD_CMD_VEVENTQ_ALLOC")
Link: https://patch.msgid.link/r/20250328114654.55840-1-bagasdotme@gmail.com
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/linux-next/20250318213359.5dc56fd1@canb.auug.org.au/
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Author: bagasme

include/uapi/linux/iommufd.h

@@ -1045,21 +1045,26 @@ enum iommu_veventq_flag {
  *            [0, INT_MAX] where the following index of INT_MAX is 0
  *
  * Each iommufd_vevent_header reports a sequence index of the following vEVENT:
- *  -------------------------------------------------------------------------
+ *
+ * +----------------------+-------+----------------------+-------+---+-------+
  * | header0 {sequence=0} | data0 | header1 {sequence=1} | data1 |...| dataN |
- *  -------------------------------------------------------------------------
+ * +----------------------+-------+----------------------+-------+---+-------+
+ *
  * And this sequence index is expected to be monotonic to the sequence index of
  * the previous vEVENT. If two adjacent sequence indexes has a delta larger than
  * 1, it means that delta - 1 number of vEVENTs has lost, e.g. two lost vEVENTs:
- *  -------------------------------------------------------------------------
+ *
+ * +-----+----------------------+-------+----------------------+-------+-----+
  * | ... | header3 {sequence=3} | data3 | header6 {sequence=6} | data6 | ... |
- *  -------------------------------------------------------------------------
+ * +-----+----------------------+-------+----------------------+-------+-----+
+ *
  * If a vEVENT lost at the tail of the vEVENTQ and there is no following vEVENT
  * providing the next sequence index, an IOMMU_VEVENTQ_FLAG_LOST_EVENTS header
  * would be added to the tail, and no data would follow this header:
- *  ---------------------------------------------------------------------------
+ *
+ * +--+----------------------+-------+-----------------------------------------+
  * |..| header3 {sequence=3} | data3 | header4 {flags=LOST_EVENTS, sequence=4} |
- *  ---------------------------------------------------------------------------
+ * +--+----------------------+-------+-----------------------------------------+
  */
 struct iommufd_vevent_header {
 	__u32 flags;
@@ -1117,9 +1122,11 @@ struct iommu_vevent_arm_smmuv3 {
  *
  * Each vEVENT in a vEVENTQ encloses a struct iommufd_vevent_header followed by
  * a type-specific data structure, in a normal case:
- *  -------------------------------------------------------------
- * || header0 | data0 | header1 | data1 | ... | headerN | dataN ||
- *  -------------------------------------------------------------
+ *
+ * +-+---------+-------+---------+-------+-----+---------+-------+-+
+ * | | header0 | data0 | header1 | data1 | ... | headerN | dataN | |
+ * +-+---------+-------+---------+-------+-----+---------+-------+-+
+ *
  * unless a tailing IOMMU_VEVENTQ_FLAG_LOST_EVENTS header is logged (refer to
  * struct iommufd_vevent_header).
  */