When new files and directories are created inside a parent directory
we automatically inherit the GFS2_DIF_SYSTEM flag (if set) and assign
it to the new file/dirs.

All new system files/dirs created in the metafs by, say gfs2_jadd,
will have this flag set because they will have parent directories in
the metafs whose GFS2_DIF_SYSTEM flag has already been set (most likely
by a previous mkfs.gfs2)
Signed-off-by: NAbhi Das <adas@redhat.com>
Signed-off-by: NBob Peterson <rpeterso@redhat.com>