fix: refactor locks to apply them uniquely per node (#11052)

This refactor is done for few reasons below

- to avoid deadlocks in scenarios when number
  of nodes are smaller < actual erasure stripe
  count where in N participating local lockers
  can lead to deadlocks across systems.

- avoids expiry routines to run 1000 of separate
  network operations and routes per disk where
  as each of them are still accessing one single
  local entity.

- it is ideal to have since globalLockServer
  per instance.

- In a 32node deployment however, each server
  group is still concentrated towards the
  same set of lockers that partipicate during
  the write/read phase, unlike previous minio/dsync
  implementation - this potentially avoids send
  32 requests instead we will still send at max
  requests of unique nodes participating in a
  write/read phase.

- reduces overall chattiness on smaller setups.

cmd/endpoint.go

@@ -242,6 +242,22 @@ func (l *EndpointServerPools) Add(zeps ZoneEndpoints) error {
 	return nil
 }
 
+// Localhost - returns the local hostname from list of endpoints
+func (l EndpointServerPools) Localhost() string {
+	for _, ep := range l {
+		for _, endpoint := range ep.Endpoints {
+			if endpoint.IsLocal {
+				u := &url.URL{
+					Scheme: endpoint.Scheme,
+					Host:   endpoint.Host,
+				}
+				return u.String()
+			}
+		}
+	}
+	return ""
+}
+
 // FirstLocal returns true if the first endpoint is local.
 func (l EndpointServerPools) FirstLocal() bool {
 	return l[0].Endpoints[0].IsLocal