tests: fix test scripts that don't work on non-Linux systems.

Fix various tests that break on non-Linux systems; in particular,
sed -i doesn't work the same on all platforms; and try to keep the
GNU getopt-isms out.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
45 files changed