ARM: mach-shmobile: Kota2 PINT fix

Support PINT on sh73a0 and Kota2 using INTC PINT macros.

With this patch applied the Kota2 ethernet is handled
through one of the chained sh73a0 PINT interrupt controllers.

sh73a0 PINT support is included in 3.2-rc but the Kota2 board
code does not make use of this shared code base without this
patch. Without this patch kota2 on-board ethernet is broken.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>