x86/UV: Add summary of cpu activity to UV NMI handler

x86/UV: Add summary of cpu activity to UV NMI handler

The standard NMI handler dumps the states of all the cpus.  This
includes a full register dump and stack trace.  This can be way
more information than what is needed.  This patch adds a
"summary" dump that is basically a form of the "ps" command.  It
includes the symbolic IP address as well as the command field
and basic process information.

It is enabled when the nmi action is changed to "ips".

Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Dimitri Sivanich <sivanich@sgi.com>
Reviewed-by: Hedi Berriche <hedi@sgi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Jason Wessel <jason.wessel@windriver.com>
Link: http://lkml.kernel.org/r/20130923212500.507922930@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>