CI: Make more use of git safe.directory

We have a number of jobs that will have git complain about needing to
set safe.directory and this being untrue as a fatal error, but then
complete. Set this flag correctly now as it should be used, and may
prevent a future failure.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>