gallium/st + hgl: Build fixes for Haiku

* No impact risk to any other platforms
* Tracing printf needs stdio.h now due to child header change
* Add missing #/src include directory for util/macros.h

src/gallium/state_trackers/hgl/hgl.c

@@ -10,6 +10,8 @@
 
 #include "GLView.h"
 
+#include <stdio.h>
+
 #include "pipe/p_format.h"
 #include "util/u_atomic.h"
 #include "util/u_format.h"

src/gallium/targets/haiku-softpipe/GalliumContext.cpp

@@ -10,6 +10,8 @@
 
 #include "GalliumContext.h"
 
+#include <stdio.h>
+
 #include "GLView.h"
 
 #include "bitmap_wrapper.h"

src/hgl/SConscript

@@ -6,6 +6,7 @@ Import('*')
 env = env.Clone()
 
 env.Append(CPPPATH = [
+    '#/src',
     '#/src/mapi',
     '#/src/mesa',
     '#/src/mesa/main',