refactor struts.RequestedDevice to have its own Equals

nomad/structs/structs.go

@@ -2136,6 +2136,34 @@ type RequestedDevice struct {
 	Affinities []*Affinity
 }
 
+func (r *RequestedDevice) Equals(o *RequestedDevice) bool {
+	if r.Name == o.Name &&
+		r.Count == o.Count {
+
+		// r.Constraints == o.Constraints, order sensitive
+		if len(r.Constraints) != len(o.Constraints) {
+			return false
+		}
+		for i, c := range r.Constraints {
+			if !c.Equal(o.Constraints[i]) {
+				return false
+			}
+		}
+
+		// r.Affinities == o.Affinities, order sensitive
+		if len(r.Affinities) != len(o.Affinities) {
+			return false
+		}
+		for i, a := range r.Affinities {
+			if !a.Equal(o.Affinities[i]) {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}
+
 func (r *RequestedDevice) Copy() *RequestedDevice {
 	if r == nil {
 		return nil