scons: always set __STDC_*_MACROS for C++ sources

Analogous to previous commit - just set the lot once throughout.

Cc: Jose Fonseca <jfonseca@vmware.com>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Reviewed-by: Jose Fonseca <jfonseca@vmware.com>

scons/gallium.py

@@ -291,8 +291,9 @@ def generate(env):
     # C preprocessor options
     cppdefines = []
     cppdefines += [
-        '__STDC_LIMIT_MACROS',
         '__STDC_CONSTANT_MACROS',
+        '__STDC_FORMAT_MACROS',
+        '__STDC_LIMIT_MACROS',
         'HAVE_NO_AUTOCONF',
     ]
     if env['build'] in ('debug', 'checked'):