scons: override the platform instead of using the host one - fixes build issues on non-linux systems

SVN-Revision: 31620

include/scons.mk

@@ -1,3 +1,5 @@
+export PLATFORM=posix
+
 SCONS_VARS = \
 	CC="$(TARGET_CC)" \
 	CXX="$(TARGET_CXX)" \

tools/scons/patches/001-platform_env.patch

@@ -0,0 +1,11 @@
+--- a/engine/SCons/Platform/__init__.py
++++ b/engine/SCons/Platform/__init__.py
+@@ -63,6 +63,8 @@ def platform_default():
+     care about the machine architecture.
+     """
+     osname = os.name
++    if 'PLATFORM' in os.environ:
++        return os.environ['PLATFORM']
+     if osname == 'java':
+         osname = os._osType
+     if osname == 'posix':