[PATCH 0/2] MR7417: mfplat: Modify MFCreateWaveFormatExFromMFMediaType to allow MF_MT_AM_FORMAT_TYPE to be missing or set to GUID_NULL.

[Brendan McGrath (＠redmcg)]

This MR:
- adds tests for when MF_MT_AM_FORMAT_TYPE is missing or set to GUID_NULL; and
- modifies MFCreateWaveFormatExFromMFMediaType to pass these tests