[VOL-4120] openonu-adapter-go: support command "voltctl device onuimage list <onu-id>"

Change-Id: If6bc1a94663c09881059b1f91d34944dccec52f3
diff --git a/internal/pkg/onuadaptercore/onu_device_entry.go b/internal/pkg/onuadaptercore/onu_device_entry.go
index 9544efa..4ada5d9 100644
--- a/internal/pkg/onuadaptercore/onu_device_entry.go
+++ b/internal/pkg/onuadaptercore/onu_device_entry.go
@@ -213,6 +213,10 @@
 	//swIsInactive = 0  not yet used
 	swIsActive = 1
 )
+const ( //definitions as per G.988 softwareImage::IsValid
+	//swIsInvalid = 0  not yet used
+	swIsValid = 1
+)
 const onuDataMeID = 0
 const onugMeID = 0
 const onu2gMeID = 0
@@ -279,6 +283,8 @@
 	onuKVStoreProcResult      error //error indication of processing
 	chOnuKvProcessingStep     chan uint8
 	onuSwImageIndications     sSwImageIndications
+	mutexOnuImageStatus       sync.RWMutex
+	pOnuImageStatus           *OnuImageStatus
 	//lockDeviceEntries           sync.RWMutex
 	mibDbClass    func(context.Context) error
 	supportedFsms OmciDeviceFsms