Remove python_sitearch.

ibus.spec.in

@@ -1,5 +1,4 @@
 %{!?python_sitelib: %define python_sitelib %(%{__python} -c "from distutils.sysconfig import get_python_lib; print get_python_lib()")}
-%{!?python_sitearch: %define python_sitearch %(%{__python} -c "from distutils.sysconfig import get_python_lib; print get_python_lib(1)")}
 %define mod_path ibus-@PACKAGE_VERSION_MAJOR@.@PACKAGE_VERSION_MINOR@
 Name:       ibus
 Version:    @PACKAGE_VERSION@