tools lib traceevent: update KVM plugin

The format of the role word has changed through the years and the plugin
was never updated; some VMX exit reasons were missing too.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/1443695293-31127-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>