[SPARC]: sparc32 side of of_device layer IRQ resolution.

Happily, life is much simpler on 32-bit sparc systems.
The "intr" property, preferred over the "interrupts"
property is used-as.  Some minor translations of this
value happen on sun4d systems.

The stage is now set to rewrite the sparc serial driver
probing to use the of_driver framework, and then to convert
all SBUS, EBUS, and ISA drivers in-kind so that we can nuke
all those special bus frameworks.

Signed-off-by: David S. Miller <davem@davemloft.net>