A patch to simplify the MD interrupt code a bit..

[John Baldwin]

This patch adds an MI intr_event_handle() routine for the non-FILTER case so 
that the MD code becomes identical in both cases and all the INTR_FILTER 
#ifdef's end up in kern_intr.c.  It's been tested on amd64, i386, and sparc64 
and cross-compiled on ppc, arm, and ia64.  I'd like to get it tested on arm 
as I slightly adjusted the MD code to just not bother masking the interrupt 
unless we are going to run an ithread which is mostly what the existing 
FILTER code did except that it unmasked the interrupt when it wasn't masked 
in the first place if a filter handled the interrupt.  Patch is at 
http://www.freebsd.org/~jhb/patches/intr_filter.patch

-- 
John Baldwin