Revert "mx6: ddr: Allow changing REFSEL and REFR fields"

This reverts commit edf0093732 for
cm_fx6 iMX.6 Solo module as it causes frequent (around 10 percent of
power cycles) board's hangs.

These hangs happen in SPL when BSS is being initialized in SDRAM -
it appear that variables from BSS contain trash values which lead to board
hangs. Looks like that SDRAM doesn't yet finish initialization in these
cases.

Signed-off-by: Maxim Yu. Osipov <mosipov@ilbers.de>
Reviewed-by: Stefano Babic <sbabic@denx.de>

board/compulab/cm_fx6/spl.c

@@ -107,8 +107,6 @@ static struct mx6_ddr_sysinfo cm_fx6_sysinfo_s = {
 	.mif3_mode	= 3,
 	.rst_to_cke	= 0x23,
 	.sde_to_rst	= 0x10,
-	.refsel = 1,		/* Refresh cycles at 32KHz */
-	.refr = 7,		/* 8 refresh commands per refresh cycle */
 };
 
 static struct mx6_ddr3_cfg cm_fx6_ddr3_cfg_s = {