Change autox scons to get more environment variables

src/platform/autox/SConstruct

Index: src/platform/autox/SConstruct
diff --git a/src/platform/autox/SConstruct b/src/platform/autox/SConstruct
index e4c4565ad62fde8576492fb77002a345a8882b0c..5ca4c58833cbfd6858aa3271af17cf2fb93527fc 100644
--- a/src/platform/autox/SConstruct
+++ b/src/platform/autox/SConstruct
@@ -16,8 +16,8 @@ for key in Split('CFLAGS CCFLAGS CPPPATH LIBPATH'):
 if not env.get('CCFLAGS'):
   env.Append(CCFLAGS=Split('-I.. -Wall -Werror -O3'))
 
-# Fix issue with scons not passing pkg-config vars through the environment.
-for key in Split('PKG_CONFIG_LIBDIR PKG_CONFIG_PATH'):
+# Fix issue with scons not passing some vars through the environment.
+for key in Split('PKG_CONFIG_LIBDIR PKG_CONFIG_PATH SYSROOT'):
   if os.environ.has_key(key):
     env['ENV'][key] = os.environ[key]