leds: Do not guard NEW_LEDS with HAS_IOMEM

The LEDS infrastructure itself does not require anything
that a platform dependant upon HAS_IOMEM.

The individual drivers do, but they are properly guarded
with the necessary platform dependencies.

One can even imagine a hypervisor based LED driver that
a platform without HAS_IOMEM might have.

Signed-off-by: David S. Miller <davem@davemloft.net>