Opening paths that are detected as archives which contain
'%[0-9A-Fa-f][0-9A-Fa-f]' will fail, because such sequence is treated as
a percent-encoded value when the path gets unescaped causing the path to
be mangled. Escape '%' to prevent this from happening.
Fixes: 2b280f4522 ("stream: libarchive wrapper for reading compressed archives")