perf tools: Fix tracepoint id to string perf.data header table

It was broken by f006d25a that passed just the event name, not the complete
sys:event that it expected to open the /sys/.../sys/sys:event/id file to get
the id.

Fix it by moving it to after parse_events in cmd_record, as at that point
we can just traverse the evsel_list and use evsel->attr.config +
event_name(evsel) instead of re-opening the /id file.

Reported-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Cc: Franck Bui-Huu <vagabon.xyz@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Han Pingtian <phan@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20110117202801.GG2085@ghostprotocols.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>