ndef: Workaround buggy Android 4.1 BT handover implementation

ndef: Workaround buggy Android 4.1 BT handover implementation

Some implementations (e.g. Android 4.1) stores the data_size in big
endian but NDEF forum spec (BT Secure Simple Pairing) requires a little
endian. At the same time, the NDEF forum NDEF spec define a payload
length as single byte (and the payload size IS the oob data size).
So we check the first byte to determine if we have a big or little
endian size.