added errname linter and changed error names to fit naming convention

.golangci.yml

cli/adapter/PndAdapter.go

controller/eventService/Service.go

controller/interfaces/plugin/plugin.go

controller/northbound/server/pnd.go

controller/nucleus/databaseDeviceStore.go

controller/nucleus/databasePndStore.go

controller/nucleus/databaseSbiStore.go

controller/nucleus/device.go

controller/nucleus/deviceFilesystemStore.go

controller/nucleus/deviceWatcher.go

controller/nucleus/errors/errors.go

controller/nucleus/gnmi_transport.go

controller/nucleus/memoryDeviceStore.go

controller/nucleus/memoryPndStore.go

controller/nucleus/memorySbiStore.go

controller/nucleus/plugin.go

controller/nucleus/pndFilesystemStore.go

controller/nucleus/principalNetworkDomain.go

controller/nucleus/restconf_transport.go