msi: introduce ARCH_SUPPORTS_MSI Kconfig option (rev2)

Allows architectures to advertise that they support MSI rather than listing
each architecture as a PCI_MSI dependency.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig
index 53d6237..bcf2fc4 100644
--- a/arch/i386/Kconfig
+++ b/arch/i386/Kconfig
@@ -1073,6 +1073,7 @@
 	bool "PCI support" if !X86_VISWS
 	depends on !X86_VOYAGER
 	default y if X86_VISWS
+	select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
 	help
 	  Find out whether you have a PCI motherboard. PCI is the name of a
 	  bus system, i.e. the way the CPU talks to the other stuff inside