This driver can be built on arm64 but relies on NO_IRQ to check the return
value of irq_of_parse_and_map() which fails to build on arm64 because the
architecture does not provide a NO_IRQ. Fix this to correctly check the
return value of irq_of_parse_and_map().

Even on ARM systems where the driver was previously used the check was
broken since on ARM NO_IRQ is -1 but irq_of_parse_and_map() returns 0 on
error.
Signed-off-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>