Fix the problem that pci_enable_msi() fails on ia64 platform. The cause of
this problem is incorrect return value of ia64_setup_msi_irq(). It must
return 0 on success, instead of irq number.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Tony Luck <tony.luck@intel.com>