ARM: kconfig: allow PCI support to be selected with ARCH_MULTIPLATFORM

When targetting ARCH_MULTIPLATFORM, we may include support for SoCs with
PCI-capable devices (e.g. mach-virt with virtio-pci).

This patch allows PCI support to be selected for these SoCs by selecting
CONFIG_MIGHT_HAVE_PCI when CONFIG_ARCH_MULTIPLATFORM=y and removes the
individual selections from multi-platform enabled SoCs.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index db3c541..860bea8 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -314,6 +314,7 @@
 	select CLKSRC_OF
 	select COMMON_CLK
 	select GENERIC_CLOCKEVENTS
+	select MIGHT_HAVE_PCI
 	select MULTI_IRQ_HANDLER
 	select SPARSE_IRQ
 	select USE_OF