sysutils/fusefs-ext2: Allow default_permissions override

The fuse-ext2 program always enables the default_permissions and
allow_other options. This is wrong. The user should be able to override
those.

Since upstream appears to be unmaintained (no commits for 3 years),
patch this bug locally.

PR: 273586
(cherry picked from commit 90d93d75b9d18e66b76d0b30b9675e7928b93bc5)