ARM: clps711x: Add FIQ interrupt handling

CLPS711X-target CPU can have a several FIQ interrupts. With this patch
we adds handling for a one which will be used for ALSA PCM later.
Since FIQ have a separate handler we only add "mask" and "unmask" calls
which will used for enable/disable_irq functions.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Olof Johansson <olof@lixom.net>