[Bug-cpio] --stop-after-found

[Dan Jacobson]

Add feature to somehow stop after finding the file.
cpio --stop-after-found -t file
cpio --stop-after-found -i file
as often no need to go on looking through the entire archive
or say in the docs to hit ^C after seeing the file on
cpio -t file
or (after a few seconds to be sure extraction is done?)
cpio -iv file