LU-15046 tests: skip sanity-flr/test_200c for old MDS

LU-15046 tests: skip sanity-flr/test_200c for old MDS

Skip sanity-flr test_200c for old MDS missing the fix
for synchronized replicas and its corresponding test.

Fixes: b7ec0d2390 ("LU-15046 osp: precreate thread vs connect race")
Test-Parameters: trivial testlist=sanity-flr env=ONLY=200c
Signed-off-by: Alex Deiter <adeiter@tintri.com>
Change-Id: I87cd7d6b767086f993a27ce6905b05f87e325474
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/51649
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Sarah Liu <sarah@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>