powerpc/86xx: mpc8610_hpcd - add support for ULI RTC

The ULI "Super South Bridge" contains ISA bridge to the legacy
devices, such as Super IO mouse/keyboard/floppy disk controllers,
parallel port, i8259 interrupt controller and so on.

i8259 is disabled on the MPC8610HPCD, and other peripherals are not
traced out. So we use only RTC.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>