LU-11596 tests: skip sanity test_64d for ARM

LU-11596 tests: skip sanity test_64d for ARM

Add sanity.sh test_64d to the ALWAYS_EXCEPT list for this bug for
ARM, since it is also intermittently failing.

Test-Parameters: trivial clientarch=aarch64 testlist=sanity
Test-Parameters: testgroup=review-dne-part-1 testlist=sanity
Test-Parameters: testgroup=review-dne-zfs-part-1 testlist=sanity
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Change-Id: Ifd52aa33d9bbf27303341ff0314322765b3ebbe5
Reviewed-on: https://review.whamcloud.com/34432
Tested-by: Jenkins
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Nunez <jnunez@whamcloud.com>
Reviewed-by: Jian Yu <yujian@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>