This patch adds single bitmap register support to intc. The current
code only handles 16 and 32 bit registers where a set bit means
interrupt enabled, but this is easy to extend in the future.

The INTC_IRQ() macro is also added to provide a way to hook in
interrupt controllers for FPGAs in boards or companion chips.
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This patch improves intc group support, ie it makes it possible to
group interrupts together and mask / unmask the entire group. This
also works with priorities, so setting a priority for an entire group
is also possible. This patch is needed to properly support certain
processors such as the 7780.

Fixes for NULL pointers in DECLARE_INTC_DESC() are also included.
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This is the second version of the shared interrupt controller patch
for the sh architecture, fixing up handling of intc_reg_fns[].

The three main advantages with this controller over the existing
ones are:

	- Both priority (ipr) and bitmap (intc2) registers are
	  supported
	- External pin sense configuration is supported, ie edge
	  vs level triggered
	- CPU/Board specific code maps 1:1 with datasheet for
	  easy verification

This controller can easily coexist with the current IPR and INTC2
controllers, but the idea is that CPUs/Boards should be moved over
to this controller over time so we have a single code base to
maintain.
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>