VOL-2154 : Moving back db/model to voltha-go

- Kept backend.go to limit impact in other components

Amendments:

- Removed db/model unit tests
- Forgot to fix some stash merges
- Removed unused "lock" parameter from kv clients
- Changed version for release

Change-Id: I25a03eb335ce22d49412be4bf2cceaff387dc4ae
diff --git a/pkg/techprofile/tech_profile_if.go b/pkg/techprofile/tech_profile_if.go
index 0904d7e..3267759 100644
--- a/pkg/techprofile/tech_profile_if.go
+++ b/pkg/techprofile/tech_profile_if.go
@@ -17,12 +17,12 @@
 package techprofile
 
 import (
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
+	"github.com/opencord/voltha-lib-go/v2/pkg/db"
 	tp_pb "github.com/opencord/voltha-protos/v2/go/tech_profile"
 )
 
 type TechProfileIf interface {
-	SetKVClient() *model.Backend
+	SetKVClient() *db.Backend
 	GetTechProfileInstanceKVPath(techProfiletblID uint32, uniPortName string) string
 	GetTPInstanceFromKVStore(techProfiletblID uint32, path string) (*TechProfile, error)
 	CreateTechProfInstance(techProfiletblID uint32, uniPortName string, intfId uint32) *TechProfile