Add optional RSS setup to interface RPS script

Adds a second parameter as an RSS pattern match in
/proc/interrupts for finding the RSS IRQs that match
the RPS queues.  If specified, it will be used to do
matching RSS+RPS assignments to the CPUs.  The pattern
must contain a "%d" placeholder for the location
of the queue number in the interrupt action name.

Unfortunately I haven't found any generic way to
figure out the RSS IRQ action name automagically, or
to avoid text-parsing /proc/interrupts.  The parameter,
when used, will be driver/hardware -specific.

This also disables irqbalance if RSS is in use.

Change-Id: Ib51ad49935e86d858362c5f8df3d6c16bbe21a6b