LU-13617 tests: check client deadlock selinux

LU-13617 tests: check client deadlock selinux

The patch adds test_20e to sanity-selinux. It checks client deadlock
and MDS eviction for it.

Test-Parameters: trivial testlist=sanity-selinux env=ONLY=20e
Signed-off-by: Alexander Boyko <alexander.boyko@hpe.com>
Cray-bug-id: LUS-8924
Change-Id: If7707fa14f7307fb3a3fb2228fbd1983b55cbe6b
Reviewed-on: https://review.whamcloud.com/38793
Reviewed-by: Sebastien Buisson <sbuisson@ddn.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andrew Perepechko <andrew.perepechko@hpe.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>