selftests/bpf: Update bpftool's consistency script for checking options

Update the script responsible for checking that the different types used
at various places in bpftool are synchronised, and extend it to check
the consistency of options between the help messages in the source code
and the manual pages.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210730215435.7095-6-quentin@isovalent.com