perf tools: Convert to GTK2_SUPPORT

For building perf without gtk+2, we can set NO_GTK2=1 as a argument of
make.  It then defines NO_GTK2_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/1348824728-14025-8-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/cache.h b/tools/perf/util/cache.h
index 70f318d..07aec06 100644
--- a/tools/perf/util/cache.h
+++ b/tools/perf/util/cache.h
@@ -33,14 +33,7 @@
 
 extern int use_browser;
 
-#if !defined(NEWT_SUPPORT) && defined(NO_GTK2_SUPPORT)
-static inline void setup_browser(bool fallback_to_pager)
-{
-	if (fallback_to_pager)
-		setup_pager();
-}
-static inline void exit_browser(bool wait_for_ok __maybe_unused) {}
-#else
+#if defined(NEWT_SUPPORT) || defined(GTK2_SUPPORT)
 void setup_browser(bool fallback_to_pager);
 void exit_browser(bool wait_for_ok);
 
@@ -55,17 +48,26 @@
 static inline void ui__exit(bool wait_for_ok __maybe_unused) {}
 #endif
 
-#ifdef NO_GTK2_SUPPORT
+#ifdef GTK2_SUPPORT
+int perf_gtk__init(void);
+void perf_gtk__exit(bool wait_for_ok);
+#else
 static inline int perf_gtk__init(void)
 {
 	return -1;
 }
 static inline void perf_gtk__exit(bool wait_for_ok __maybe_unused) {}
-#else
-int perf_gtk__init(void);
-void perf_gtk__exit(bool wait_for_ok);
 #endif
-#endif /* !NEWT_SUPPORT && NO_GTK2_SUPPORT */
+
+#else /* NEWT_SUPPORT || GTK2_SUPPORT */
+
+static inline void setup_browser(bool fallback_to_pager)
+{
+	if (fallback_to_pager)
+		setup_pager();
+}
+static inline void exit_browser(bool wait_for_ok __maybe_unused) {}
+#endif /* NEWT_SUPPORT || GTK2_SUPPORT */
 
 char *alias_lookup(const char *alias);
 int split_cmdline(char *cmdline, const char ***argv);