python3-pyelftools: Depend on debugger, pprint

python3-pyelftools uses python3-debugger, python3-pprint.
So add dependencies on these packages.

Signed-off-by: Chaitanya Vadrevu <chaitanya.vadrevu@ni.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit 22e84cdd)
Signed-off-by: Anuj Mittal <anuj.mittal@intel.com>