Please always send patches against the current mainline; the "tilegx_return_value"
function had a function signature that is no longer correct in mainline, and thus
caused an --enable-targets=all build to fail. I've fixed it.
I've also went through the patch and updated a series of formatting
issues (tabs/spaces, some alignments, etc.) and a few typos/pastos, as it was more
efficient that more back and forth. ;-) I've also done a couple other minor
things, like adding multiple inclusion guards to tilegx-tdep.h.
Here's the patch as checked in.