x86/msi: Fix msi message data shadow struct

x86/msi: Fix msi message data shadow struct

commit 59b18a1e65b7a2134814106d0860010e10babe18 upstream.

The x86 MSI message data is 32 bits in total and is either in
compatibility or remappable format, see Intel Virtualization Technology
for Directed I/O, section 5.1.2.

Fixes: 6285aa50736 ("x86/msi: Provide msi message shadow structs")
Co-developed-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Reto Buerki <reet@codelabs.ch>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220407110647.67372-1-reet@codelabs.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>