tile: Use SPARSE_IRQ

Get rid of the private allocator and switch over to sparse IRQs.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Link: http://lkml.kernel.org/r/20140507154338.423715783@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>