socks5: use ${PORTAGE_TMPDIR}/portage (bug 683040)

Write temporary socket files in ${PORTAGE_TMPDIR}/portage,
since writing files directly in ${PORTAGE_TMPDIR} is generally
unexpected.

Bug: https://bugs.gentoo.org/683040
Signed-off-by: Zac Medico <zmedico@gentoo.org>
1 file changed