[IA64-SGI] revert export sn_pcidev_info_get

Christoph Hellwig <hch@infradead.org> pointed that there are no
in-tree uses of this.  So revert 9c65cb9bSigned-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/sn/kernel/io_init.c

@@ -716,4 +716,3 @@ EXPORT_SYMBOL(sn_pci_unfixup_slot);
 EXPORT_SYMBOL(sn_pci_controller_fixup);
 EXPORT_SYMBOL(sn_bus_store_sysdata);
 EXPORT_SYMBOL(sn_bus_free_sysdata);
-EXPORT_SYMBOL(sn_pcidev_info_get);