fix superframe index marker masks

The superframe index marker byte carries data in the lower 5 bits. Only the
upper 3 should be used as part of the mask to detect it. By masking with
0xf0, the previous code was incorrect for frames over 65k bytes.

Change-Id: I6248889f5af227457f359a56b2348ef6db87a3b4
2 files changed