PCI: Only build PCI syscalls on architectures that want them

The PCI syscalls are built on every architecture except X86, but only
a few have ever hooked them up.  Use a new Kconfig symbol to save a
couple of kB on the architectures that have never used the syscalls.
Tested on x86 and ia64 only.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index fbcc00c..8567cc9 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -210,6 +210,9 @@
 	  CP-1200, JavaEngine-1, Corona, Red October, and Serengeti SGSC.
 	  All of these platforms are extremely obscure, so say N if unsure.
 
+config PCI_SYSCALL
+	def_bool PCI
+
 source "drivers/pci/Kconfig"
 
 endif