x86, io-apic: Remove !irq_remapped() check from __target_IO_APIC_irq()

This function is only called from default_ioapic_set_affinity()
which is only used when interrupt remapping is disabled
since the introduction of the set_affinity function pointer.
So the check will always evaluate as true and can be
removed.

Signed-off-by: Joerg Roedel <joro@8bytes.org>
Acked-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>