64.6.10.12 Endianness

If the QSPI is not configured in Octal DDR mode, endianness does not matter and QSPI_IFER.END should be left at 0 (default=little-endian).

When the QSPI is configured in Octal DDR mode, halfwords are sent/received instead of bytes. Endianness must be configured according to the memory data sheet.