sh: Kill off machvec IRQ hinting.

Everything is using sparseirq these days, so we have no need to
arbitrarily size nr_irqs ahead of time. The legacy IRQ pre-allocation
likewise has no meaning for us, so that's killed off too. We now depend
on nr_irqs expansion by the generic hardirq layer instead.

It's also worth noting that the majority of boards had completely bogus
values for their nr_irqs relative to their CPU and configurations, so
this ends up correcting behaviour for quite a few platforms.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/boards/mach-se/7721/setup.c

@@ -92,6 +92,5 @@ static void __init se7721_setup(char **cmdline_p)
 struct sh_machine_vector mv_se7721 __initmv = {
 	.mv_name		= "Solution Engine 7721",
 	.mv_setup		= se7721_setup,
-	.mv_nr_irqs		= 109,
 	.mv_init_irq		= init_se7721_IRQ,
 };