perf tools: Factorize the map helpers

Factorize the dso mapping helpers into a single purpose common file
"util/map.c"

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Brice Goglin <Brice.Goglin@inria.fr>
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 718b8f7..106c6ab 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -15,6 +15,7 @@
 #include "util/string.h"
 
 #include "util/header.h"
+#include "util/event.h"
 
 #include <unistd.h>
 #include <sched.h>