[PATCH] Suppress 'unused function' warnings on specialized template functions

[Rafael Espíndola]

> Attached is an updated patch file that includes a test case.

Thanks. Some general comments:

* Try to stay under 80 columns.
* Avoid trailing white space.
* If possible, include the test into an existing generic test. Can you
add these to test/SemaCXX/warn-unused-filescoped.cpp?

And specific to this patch, I think FD->getCanonicalDecl will give you
the right answer for all kinds of FunctionDecl, no?

Thanks,
Rafael