misc-functions.sh: restore canonicalize func (bug 675284)

The canonicalize function is required by install-qa-check.d/05prefix.

Fixes: aa0a94198794 ("ecompress: Replace with implementation from portage[mgorny]")
Bug: https://bugs.gentoo.org/670484
Signed-off-by: Zac Medico <zmedico@gentoo.org>
2 files changed