perf tools: Always try to build libtraceevent

Although perf depends on the libtraceevent, it cannot know when it needs
to be rebuilt. So just try to rebuild it always in order to make sure we
use the latest version.

While at it, silence annoying directory change messages.

Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1337677434-4881-2-git-send-email-namhyung.kim@lge.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Makefile

@@ -828,7 +828,7 @@ $(LIB_FILE): $(LIB_OBJS)
 
 # libtraceevent.a
 $(LIBTRACEEVENT):
-	$(MAKE) -C $(TRACE_EVENT_DIR) $(COMMAND_O) libtraceevent.a
+	$(QUIET_SUBDIR0)$(TRACE_EVENT_DIR) $(QUIET_SUBDIR1) $(COMMAND_O) libtraceevent.a
 
 help:
 	@echo 'Perf make targets:'
@@ -976,6 +976,6 @@ clean:
 	$(RM) $(OUTPUT)util/*-{bison,flex}*
 	$(python-clean)
 
-.PHONY: all install clean strip
+.PHONY: all install clean strip $(LIBTRACEEVENT)
 .PHONY: shell_compatibility_test please_set_SHELL_PATH_to_a_more_modern_shell
 .PHONY: .FORCE-PERF-VERSION-FILE TAGS tags cscope .FORCE-PERF-CFLAGS