Fix leak of DeviceTransportMgr in CHIPDeviceController (#4415)
Fix leak of DeviceTransportMgr in CHIPDeviceController (#4415)

* Fix leak of DeviceTransportMgr in CHIPDeviceController

DeviceTransportMgr is created in Init() but not deleted in Shutdown().

* Restyled by clang-format

Co-authored-by: Restyled.io <eb8d3fd3977bb570908ffc25e24391520747defb@restyled.io>
nestlabs/connectedhomeip,project-chip/connectedhomeip,nestlabs/connectedhomeip,nestlabs/connectedhomeip,project-chip/connectedhomeip,project-chip/connectedhomeip,project-chip/connectedhomeip,nestlabs/connectedhomeip,nestlabs/connectedhomeip,project-chip/connectedhomeip,nestlabs/connectedhomeip,nestlabs/connectedhomeip,project-chip/connectedhomeip