After converstion to SPARSE_IRQ, the driver doesn't use the
pdata->irq_base/irq_end fields anymore.  The last users
have been cleanup up, and now these fields can be removed.

Cc: Benoit Cousson <b-cousson@ti.com>
Acked-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>