XML generation for data model is failing intermittently on pipeline.

It seems os.walk() output list order is not deterministic across machines, so it is machine/OS dependent. This function is being called to get C files in bbf to create data model for them. If script creates data model for child before parent, it raises an issue. The solution is to sort files for result of os.walk(). This will make result deterministic and not machine or OS dependent.

Example of issue: os.walk() output: [.., "wifi.dataelements.c", "wifi.c", ..] results in placing objects in wifi.dataelements outside Device.wifi.