Commit b50cac5 ("PCI/sysfs: add per pci device msi[x] irq listing (v5)") added
"struct kobject" dependency to <linux/msi.h> which breaks KVM tool build. As
the header file is no longer about MSI hardware, make a new header file for
"struct msi_ms".
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Pekka Enberg <penberg@kernel.org>