The PCI_MSI symbol is used inconsistently throughout the tree, with some
drivers using 'select' and others using 'depends on', or using conditional
selects.  This keeps causing problems; the latest one is a result of
ARCH_ALPINE using a 'select' statement to enable its platform-specific MSI
driver without enabling MSI:

  warning: (ARCH_ALPINE) selects ALPINE_MSI which has unmet direct dependencies (PCI && PCI_MSI)
  drivers/irqchip/irq-alpine-msi.c:104:15: error: variable 'alpine_msix_domain_info' has initializer but incomplete type
   static struct msi_domain_info alpine_msix_domain_info = {
		 ^~~~~~~~~~~~~~~
  drivers/irqchip/irq-alpine-msi.c:105:2: error: unknown field 'flags' specified in initializer
    .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
    ^
  drivers/irqchip/irq-alpine-msi.c:105:11: error: 'MSI_FLAG_USE_DEF_DOM_OPS' undeclared here (not in a function)
    .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
	     ^~~~~~~~~~~~~~~~~~~~~~~~

There is little reason to enable PCI support for a platform that uses MSI
but then leave MSI disabled at compile time.

Select PCI_MSI from irqchips that implement MSI, and make PCI host bridges
that use MSI on ARM depend on PCI_MSI_IRQ_DOMAIN.

For all three architectures that support PCI_MSI_IRQ_DOMAIN (ARM, ARM64,
X86), enable it by default whenever MSI is enabled.

[bhelgaas: changelog, omit crypto config change]
Suggested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>