Fixed wrong compile time check.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@6335 35acf78f-673a-0410-8e92-d51de3d6d3f4
again...

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@6336 35acf78f-673a-0410-8e92-d51de3d6d3f4