Passing vector number (was Re: API modification request)

[Till Straumann]

On the idea of passing a vector number:

- it's certainly MUCH better than nothing (in this sense, the 'new'
   API present on PPC/X86 and ARM is a huge step back).

- the 'new' API could certainly pass the vector (irq->name) along.

- however, IMO it's still preferrable to have the user argument:

   1) vector number is BSP/hardware dependent (but needs to be
      known for installing the ISR anyways).
   2) On hardware where you have to lookup the handler (i.e. a slot
      a 'connect_data' table, getting the 'arg' is not far away
      (see discussion on the original thread).
   3) Makes porting vxWorks code is easier. IMO, this is important
      if we want to make migration as painless as possible.

-- Till