[IA64] Minor cleanups - remove CONFIG_ACPI_DEALLOCATE_IRQ

The config option 'CONFIG_ACPI_DEALLOCATE_IRQ' is no longer
needed. This patch removes it.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>