tests: don't disqualify FreeBSD 8.1's /bin/sh just yet,

tests: don't disqualify FreeBSD 8.1's /bin/sh just yet,

because dash-0.5.6-2.fc14.x86_64 would also be disqualified.
This reverts part of yesterday's commit 6c058b2d, "tests: avoid
failure due to bug in FreeBSD 8.1's /bin/sh".  Note that the offending
aspect of those shells is not officially a bug, since "local" is not
specified by POSIX.  However, it is very unintuitive that prepending
"local" to an existing, standards-compliant assignment would evoke
such a fundamental change in semantics.
* tests/init.sh: Remove snippet requiring sane "local" support.
Upstream dash bug report:
http://thread.gmane.org/gmane.comp.shells.dash/419