Untested ARM port related stuff.

git-svn-id: https://svn.code.sf.net/p/chibios/svn/trunk@6968 35acf78f-673a-0410-8e92-d51de3d6d3f4
git-svn-id: https://svn.code.sf.net/p/chibios/svn/trunk@6969 35acf78f-673a-0410-8e92-d51de3d6d3f4
git-svn-id: https://svn.code.sf.net/p/chibios/svn/trunk@6970 35acf78f-673a-0410-8e92-d51de3d6d3f4
Fixed bug #506.

git-svn-id: https://svn.code.sf.net/p/chibios/svn/trunk@6972 35acf78f-673a-0410-8e92-d51de3d6d3f4
Fixed bug #509.

git-svn-id: https://svn.code.sf.net/p/chibios/svn/trunk@6975 35acf78f-673a-0410-8e92-d51de3d6d3f4
Fixed bug #510.

git-svn-id: https://svn.code.sf.net/p/chibios/svn/trunk@6977 35acf78f-673a-0410-8e92-d51de3d6d3f4
git-svn-id: https://svn.code.sf.net/p/chibios/svn/trunk@6980 35acf78f-673a-0410-8e92-d51de3d6d3f4
git-svn-id: https://svn.code.sf.net/p/chibios/svn/trunk@6981 35acf78f-673a-0410-8e92-d51de3d6d3f4