The current code skips the check to verify whether the filesystem was
previously cleanly unmounted, if (flags & UFS_ST_MASK) == UFS_ST_44BSD or
UFS_ST_OLD. This looks like an inadvertent bug that slipped in due to
parantheses in the compound conditional to me, especially given that
ufs_get_fs_state() handles the UFS_ST_44BSD case perfectly well. So, let's
fix the compound condition appropriately.