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/arm/Kconfig b/arch/arm/Kconfig
index 50d9f3e..482d33f 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -531,6 +531,9 @@
 	  information about which PCI hardware does work under Linux and which
 	  doesn't.
 
+config PCI_SYSCALL
+	def_bool PCI
+
 # Select the host bridge type
 config PCI_HOST_VIA82C505
 	bool