During ptest execution, util-linux adds mount entries in /etc/fstab
and runs `mount -a`, which mounts all available entries from
/etc/fstab. This can cause unintended mounts that are unrelated to
the test, leading to incorrect test behavior.
To avoid this, upstream util-linux introduced a mechanism using
CUSTOM_FSTAB,which isolates test-specific fstab entries. Only entries
listed in CUSTOM_FSTAB are mounted during test execution, ensuring
tests do not interfere with or depend on the system's /etc/fstab.
This commit backports below upstream changes to use CUSTOM_FSTAB.
ed3d33faffb1580bd7606aa8d17b6b
(From OE-Core rev: 94747fb63518bf907eb7c09fc2e146e39e235a7d)
Signed-off-by: Virendra Thakur <virendra.thakur@kpit.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>