selftests/landlock: Add supports_filesystem() helper

Replace supports_overlayfs() with supports_filesystem() to be able to
check several filesystems.  This will be useful in a following commit.

Only check for overlay filesystem once in the setup step, and then rely
on self->skip_test.

Cc: Guenter Roeck <[email protected]>
Cc: Jeff Xu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mickaël Salaün <[email protected]>

0 files changed, 0 insertions, 0 deletions