tests: fix various timeout races

tests: fix various timeout races

Prompted by the continuous integration build failure at:
http://hydra.nixos.org/build/277485

* tests/misc/timeout: Set all expected timeouts to 1s and all
unexpected timeouts to 10s. In this way, tests normally proceed
quickly but may delay up to 10s before reporting failures.
* tests/ls/infloop: Likewise.
* tests/tail-2/pid: Likewise.
* tests/tail-2/pipe-f: Likewise.
* tests/tail-2/wait: Likewise.
* tests/dd/skip-seek-past-dev: Likewise.