rgw: increase the number of OSDs for erasure coded pools

So that there never is less than 4 osd which is the minimum when trying
erasure coded workloads that only work with 4 osd.

http://tracker.ceph.com/issues/9298 Fixes: #9298

Signed-off-by: Loic Dachary <loic-201408@dachary.org>

suites/rgw/singleton/all/radosgw-admin-data-sync.yaml

@@ -1,5 +1,5 @@
 roles:
-- [mon.a, osd.0, osd.1, client.0, client.1]
+- [mon.a, osd.0, osd.1, osd.2, osd.3, client.0, client.1]
 tasks:
 - install:
 - ceph:

suites/rgw/singleton/all/radosgw-admin-multi-region.yaml

@@ -1,6 +1,6 @@
 roles:
-- [mon.a, osd.0, osd.1, client.0]
-- [mon.b, mon.c, osd.2, osd.3, client.1]
+- [mon.a, osd.0, osd.1, osd.2, client.0]
+- [mon.b, mon.c, osd.3, osd.4, osd.5, client.1]
 tasks:
 - install: 
 - ceph:

suites/rgw/singleton/all/radosgw-admin.yaml

@@ -1,5 +1,5 @@
 roles:
-- [mon.a, osd.0, client.0, osd.1]
+- [mon.a, osd.0, client.0, osd.1, osd.2, osd.3]
 tasks:
 - install:
 - ceph:

suites/rgw/singleton/all/radosgw-convert-to-region.yaml

@@ -15,8 +15,8 @@ overrides:
         size: 2000
         stddev: 500
 roles:
-- [mon.a, osd.0, osd.1, client.0]
-- [mon.b, mon.c, osd.2, osd.3, client.1]
+- [mon.a, osd.0, osd.1, osd.2, client.0]
+- [mon.b, mon.c, osd.3, osd.4, osd.5, client.1]
 
 tasks:
 - install: