spi_atben.c (atben_probe): also make IRQ a non-function

... so that it can be used for interrupts.
at86rf230.c (at86rf230_probe): explicitly request IRQF_TRIGGER_HIGH

... instead of hoping for a suitable default. The default was good in
the past but changes at some point in time.

Note that this patch conflicts with other work currently being under
review for net-next and will probably be obsoleted soon.