MB-45756: Log purge seqno when creating VBucket

Log the purge seqno of the VBucket when creating it so we can see more
information about the vbucket state we read from disk was during warmup.

Change-Id: Ie302adbc173c768f949a61873b5f48238a989d9a
Reviewed-on: http://review.couchbase.org/c/kv_engine/+/152354
Reviewed-by: Paolo Cocchi <[email protected]>
Tested-by: Build Bot <[email protected]>

Author: rdemellow

engines/ep/src/vbucket.cc

@@ -237,13 +237,15 @@ VBucket::VBucket(Vbid i,
 
     EP_LOG_INFO(
             "VBucket: created {} with state:{} initialState:{} lastSeqno:{} "
-            "persistedRange:{{{},{}}} max_cas:{} uuid:{} topology:{}",
+            "persistedRange:{{{},{}}} purge_seqno:{} max_cas:{} uuid:{} "
+            "topology:{}",
             id,
             VBucket::toString(state),
             VBucket::toString(initialState),
             lastSeqno,
             persistedRange.getStart(),
             persistedRange.getEnd(),
+            purge_seqno,
             getMaxCas(),
             failovers ? std::to_string(failovers->getLatestUUID()) : "<>",
             replicationTopology.rlock()->dump());