perf tools: Add dsos__hit_all()

Add ability to mark all dsos as hit.

This is needed in the case of Instruction Tracing.  It takes so long to
decode an Instruction Trace that it is not worth doing just to determine
which dsos are hit.  A later patch takes this into use.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1406035081-14301-15-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/header.h

@@ -151,6 +151,8 @@ int perf_event__process_build_id(struct perf_tool *tool,
 				 struct perf_session *session);
 bool is_perf_magic(u64 magic);
 
+int dsos__hit_all(struct perf_session *session);
+
 /*
  * arch specific callback
  */