ARM: shmobile: r8a7779: Route all interrupts to ARM

Without this, the interrupts for I2C, VIN, GPIO, SDHC, HSCIF and
HPB-DMAC are sent to the SH processor.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>