Add support for split OSD adds

Allows creating multiple OSDs on a single (NVMe) block device,
leveraging the "ceph-volume lvm batch" command. Replaces the previous
method of creating OSDs.

Also adds a new ZK item for each OSD indicating if it is split or not.

api-daemon/pvcapid/helper.py

@@ -1366,12 +1366,28 @@ def ceph_osd_db_vg_add(zkhandler, node, device):
 
 
 @ZKConnection(config)
-def ceph_osd_add(zkhandler, node, device, weight, ext_db_flag=False, ext_db_ratio=0.05):
+def ceph_osd_add(
+    zkhandler,
+    node,
+    device,
+    weight,
+    ext_db_flag=False,
+    ext_db_ratio=0.05,
+    split_flag=False,
+    split_count=1,
+):
     """
     Add a Ceph OSD to the PVC Ceph storage cluster.
     """
     retflag, retdata = pvc_ceph.add_osd(
-        zkhandler, node, device, weight, ext_db_flag, ext_db_ratio
+        zkhandler,
+        node,
+        device,
+        weight,
+        ext_db_flag,
+        ext_db_ratio,
+        split_flag,
+        split_count,
     )
 
     if retflag: