Update the --help documentation and match the man page
In particular, explain how 1/2/3+ paths to udev-hid-bpf add are handled
in the --help documentation, add the lookup directories to the man page
(because we can't easily add that to --help).
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In particular, explain how 1/2/3+ paths to udev-hid-bpf add are handled
in the --help documentation, add the lookup directories to the man page
(because we can't easily add that to --help).