perf tools: Extend the event parser maximum error index

Extend the event parser maximum error index from 10 to 13.  That allows
PMU config terms of up to 10 characters to display un-truncated in the
error message.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1437150840-31811-17-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>