[PATCH] fix target_cpus() for summit subarch

[PATCH] fix target_cpus() for summit subarch

I've been hunting down a bug affecting IBM x440/x445 systems where the
floppy driver would get spurious interrupts and would not initialize
properly.

After digging James Cleverdon and Bill Irwin pointed out that target_cpus()
is routing the interrupts to the clustered apic broadcast mask using
destFixed deliver mode.  This was causing multiple interrupts to show up,
breaking the floppy init code.

This fix simply changes the delivery mode to dest_LowestPrio and initially
routes interrupts to the first cpu to resolve this issue.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>