zdtm: make cgroup testcases run non-parallel

cgroup testcases live in the same cgroup root zdtmtst and
zdtmtst.defaultroot controller then create child subgroup for testing. This
can cause problems when cgroup testcases run in parallel. For example,
testcase A dumps the child subgroup of testcase B since it's in the cgroup
root but in the middle of restoring of testcase A, testcase B completes and
cleans up the subgroup directory. This causes error in testcase A restore.
This commit adds excl flag to all cgroup testcases description so that
these don't run parallel.

Signed-off-by: Bui Quang Minh <minhquangbui99@gmail.com>

test/zdtm/static/cgroup00.desc

@@ -1 +1 @@
-{'flavor': 'h', 'flags': 'suid', 'opts': '--manage-cgroups'}
+{'flavor': 'h', 'flags': 'suid excl', 'opts': '--manage-cgroups'}

test/zdtm/static/cgroup01.desc

@@ -1 +1 @@
-{'flavor': 'h', 'flags': 'suid', 'opts': '--manage-cgroups'}
+{'flavor': 'h', 'flags': 'suid excl', 'opts': '--manage-cgroups'}

test/zdtm/static/cgroup02.desc

@@ -1,4 +1,4 @@
 {   'dopts': '--manage-cgroups --cgroup-root name=zdtmtst:/prefix',
-    'flags': 'suid',
+    'flags': 'suid excl',
     'flavor': 'h',
     'ropts': '--manage-cgroups --cgroup-root /newroot --cgroup-root name=zdtmtst:/prefix'}

test/zdtm/static/cgroup_threads.desc

@@ -1 +1 @@
-{'flavor': 'h', 'flags': 'suid', 'opts': '--manage-cgroups'}
+{'flavor': 'h', 'flags': 'suid excl', 'opts': '--manage-cgroups'}

test/zdtm/static/cgroup_yard.desc

@@ -1,6 +1,6 @@
 {
 'flavor': 'h',
-'flags': 'suid',
+'flags': 'suid excl',
 # We create the external cgroup yard in working directory during --pre-dump
 # hook. We have to go up a few directories to find the yard.
 'opts': '--manage-cgroups --cgroup-yard ../../../../../../external_yard'

test/zdtm/static/cgroupns.desc

@@ -1,4 +1,4 @@
 {   'feature': 'cgroupns',
-    'flags': 'suid',
+    'flags': 'suid excl',
     'flavor': 'h',
     'opts': '--manage-cgroups'}

test/zdtm/static/cgroupv2_00.desc

@@ -1 +1 @@
-{'flavor': 'h ns', 'flags': 'suid', 'opts': '--manage-cgroups=full'}
+{'flavor': 'h ns', 'flags': 'suid excl', 'opts': '--manage-cgroups=full'}

test/zdtm/static/cgroupv2_01.desc

@@ -1 +1 @@
-{'flavor': 'h ns', 'flags': 'suid', 'opts': '--manage-cgroups=full'}
+{'flavor': 'h ns', 'flags': 'suid excl', 'opts': '--manage-cgroups=full'}