fsl

Commit 34e026f9 added one extra bit to wr_lat for timing_cfg_2, but
with wrong bit position. It is bit 13 in big-endian, or left shift
18 from LSB. This error hasn't had any impact because we don't have
fast enough DDR4 using the extra bit so far.

Signed-off-by: York Sun <york.sun@nxp.com>