genirq/msi: Correct kernel-doc in <linux/msi.h>

genirq/msi: Correct kernel-doc in <linux/msi.h>

Eliminate all kernel-doc warnings in <linux/msi.h>:

  - add "struct" to struct kernel-doc headers
  - add missing struct member descriptions or correct typos in them

Fixes these warnings:
Warning: include/linux/msi.h:60 cannot understand function prototype:
 'struct msi_msg'
Warning: include/linux/msi.h:73 struct member 'arch_addr_lo' not described
 in 'msi_msg'
Warning: include/linux/msi.h:73 struct member 'arch_addr_hi' not described
 in 'msi_msg'
Warning: include/linux/msi.h:106 cannot understand function prototype:
 'struct pci_msi_desc'
Warning: include/linux/msi.h:124 struct member 'msi_attrib' not described
 in 'pci_msi_desc'
Warning: include/linux/msi.h:204 struct member 'sysfs_attrs' not described
 in 'msi_desc'
Warning: include/linux/msi.h:227 struct member 'domain' not described in
 'msi_dev_domain'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251214202341.2205675-1-rdunlap@infradead.org