perf kvm: Simplify exit reasons tables definitions

The perf_kvm_stat struct keeps the size of a table of exit reasons in
the field 'exit_reasons_size'.

The field is initialized and then used by get_exit_reason() for serial
access to the table, so that the calling function does not actually need
to know table size.

Usage of tables with 'end of sequence' marker simplifies the
get_exit_reason() function.

Also the patch introduces a define_exit_reasons_table, which makes it
easier to define new tables.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1404395992-17095-3-git-send-email-yarygin@linux.vnet.ibm.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>