perf tools: Convert to LIBAUDIT_SUPPORT

For building perf without libaudit, we can set NO_LIBAUDIT=1 as a
argument of make.  It then defines NO_LIBAUDIT_SUPPORT macro for C code
to do the proper handling.  However it usually used in a negative
semantics - e.g. #ifndef - so we saw double negations which can be
misleading.  Convert it to a positive form to make it more readable.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1348824728-14025-6-git-send-email-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Makefile

@@ -543,14 +543,12 @@ ifndef NO_LIBUNWIND
 	LIB_OBJS += $(OUTPUT)util/unwind.o
 endif
 
-ifdef NO_LIBAUDIT
-	BASIC_CFLAGS += -DNO_LIBAUDIT_SUPPORT
-else
+ifndef NO_LIBAUDIT
 	FLAGS_LIBAUDIT = $(ALL_CFLAGS) $(ALL_LDFLAGS) -laudit
 	ifneq ($(call try-cc,$(SOURCE_LIBAUDIT),$(FLAGS_LIBAUDIT)),y)
 		msg := $(warning No libaudit.h found, disables 'trace' tool, please install audit-libs-devel or libaudit-dev);
-		BASIC_CFLAGS += -DNO_LIBAUDIT_SUPPORT
 	else
+		BASIC_CFLAGS += -DLIBAUDIT_SUPPORT
 		BUILTIN_OBJS += $(OUTPUT)builtin-trace.o
 		EXTLIBS += -laudit
 	endif

tools/perf/perf.c

@@ -55,7 +55,7 @@ static struct cmd_struct commands[] = {
 	{ "lock",	cmd_lock,	0 },
 	{ "kvm",	cmd_kvm,	0 },
 	{ "test",	cmd_test,	0 },
-#ifndef NO_LIBAUDIT_SUPPORT
+#ifdef LIBAUDIT_SUPPORT
 	{ "trace",	cmd_trace,	0 },
 #endif
 	{ "inject",	cmd_inject,	0 },