qa: create common conf for all cephfs suites

qa: create common conf for all cephfs suites

This will be followed by removing common CephFS configurations in the
ceph.conf.template in teuthology.

Signed-off-by: Patrick Donnelly <pdonnell@redhat.com>
(cherry picked from commit 73fa0efcbb15a47157615705043288f2913ff3bc)

Conflicts:
	qa/suites/fs/32bits/overrides/debug.yaml
	qa/suites/fs/basic_functional/overrides/debug.yaml
	qa/suites/fs/basic_workload/overrides/debug.yaml
	qa/suites/fs/bugs/client_trim_caps/overrides/debug.yaml
	qa/suites/fs/multiclient/overrides/debug.yaml
	qa/suites/fs/multifs/overrides/debug.yaml
	qa/suites/fs/permission/overrides/debug.yaml
	qa/suites/fs/snaps/overrides/debug.yaml
	qa/suites/fs/upgrade/snaps/conf
	qa/suites/fs/thrash/overrides/debug.yaml
	qa/suites/fs/traceless/overrides/debug.yaml
	qa/suites/fs/verify/overrides/debug.yaml
	qa/suites/kcephfs/cephfs/overrides/debug.yaml
	qa/suites/kcephfs/mixed-clients/overrides/debug.yaml
	qa/suites/kcephfs/recovery/overrides/debug.yaml
	qa/suites/kcephfs/thrash/overrides/debug.yaml