ARM: pci: make pcibios_assign_all_busses use pci_has_flag

Convert pcibios_assign_all_busses from a define to inline so platforms can
control this setting.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/arm/mach-ixp23xx/pci.c b/arch/arm/mach-ixp23xx/pci.c
index 563819a..72d145a 100644
--- a/arch/arm/mach-ixp23xx/pci.c
+++ b/arch/arm/mach-ixp23xx/pci.c
@@ -227,6 +227,8 @@
 
 void __init ixp23xx_pci_preinit(void)
 {
+	pci_set_flags(0);
+
 	ixp23xx_pci_common_init();
 
 	hook_fault_code(16+6, ixp23xx_pci_abort_handler, SIGBUS, 0,