oe-selftest: force some values in local.conf for _sstatetests_noauto.py
1) Some values should have default values in order for tests like sstate relocation to be relevant
- SSTATE_DIR needs to have default value
- SSTATE_MIRRORS need to be unset (we need the sstate files to be created)
- TMPDIR needs to be in default location
2) Added conf/auto.conf to list of ported files to secondary build directories
Signed-off-by: Corneliu Stoicescu <corneliux.stoicescu@intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
