ls102xa: ifc: nor: fix the write issue when bytes unaligned

Add define CONFIG_SYS_WRITE_SWAPPED_DATA.
For LS1021AQDS and LS1021QTWR nor flash write should swap the
bytes when handle unaligned tail bytes.

Because of the ending, if the date bus width is 16-bits and the
number of bytes is odd, we should swap the byte when write the
last one.

Signed-off-by: Yuan Yao <yao.yuan@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>