Upgrade ATF to 0.17

Reapply r251108

Signed-off-by: Garrett Cooper <yanegomi@gmail.com>
Fix file extension pedanticisms that clang++ hates

Signed-off-by: Garrett Cooper <yanegomi@gmail.com>
Update the test list

Signed-off-by: Garrett Cooper <yanegomi@gmail.com>
Merge branch 'master' into atf-tools-regression-convert