It's called _pio_ in the version that was added to git.
Apparently it got renamed without updating the macros before it was
applied, c.f.
http://u-boot.10912.n7.nabble.com/U-Boot-PATCH-3-9-V3-add-a-new-AT91-GPIO-driver-td75922.html



Signed-off-by: Andreas Henriksson <andreas.henriksson@endian.se>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>