perf threads: Move thread_map to separate file

To untangle it from struct thread handling, that is tied to symbols, etc.

Right now in the python bindings I'm working on I need just a subset of
the util/ files, untangling it allows me to do that.

Cc: Frederic Weisbecker <fweisbec@gmail.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: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index ee49035..9a6d942 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -3,7 +3,7 @@
 #include "../perf.h"
 #include "util.h"
 #include "cpumap.h"
-#include "thread.h"
+#include "thread_map.h"
 
 #include <unistd.h>
 #include <sys/mman.h>