mx53: ddr3: Update DD3 initialization

mx53: ddr3: Update DD3 initialization

Updated mx53 ddr3 script in order to align with the latest Freescale version from July 8, 2011:
-change ESDREF[REF_SEL]=01 (for 32KHz), from incorrect setting of 00 (64KHz)
-change DDR3 MR0 write to "setmem /32 0x63fd901c = 0x052080b0" from
"0x092080b0". This changes write recovery from 8 clocks to 6 clocks
(in line with ESDCFG1[tWR])

Signed-off-by: Lily Zhang <r58066@freescale.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>