iommu/vt-d: Fix kernel-doc syntax in file header

The opening comment mark '/**' is used for highlighting the beginning of
kernel-doc comments.
The header for drivers/iommu/intel/pasid.c follows this syntax, but
the content inside does not comply with kernel-doc.

This line was probably not meant for kernel-doc parsing, but is parsed
due to the presence of kernel-doc like comment syntax(i.e, '/**'), which
causes unexpected warnings from kernel-doc:
warning: Function parameter or member 'fmt' not described in 'pr_fmt'

Provide a simple fix by replacing this occurrence with general comment
format, i.e. '/*', to prevent kernel-doc from parsing it.
Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210523143245.19040-1-yashsri421@gmail.com
Link: https://lore.kernel.org/r/20210610020115.1637656-3-baolu.lu@linux.intel.comSigned-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel/pasid.c

 // SPDX-License-Identifier: GPL-2.0
-/**
+/*
  * intel-pasid.c - PASID idr, table and entry manipulation
  *
  * Copyright (C) 2018 Intel Corporation