arm64: dts: ls1028a: fix endian setting for dcfg

DCFG block uses little endian.  Fix it so that register access becomes
correct.

Signed-off-by: Yinbo Zhu <yinbo.zhu@nxp.com>
Acked-by: Yangbo Lu <yangbo.lu@nxp.com>
Fixes: 8897f325 ("arm64: dts: Add support for NXP LS1028A SoC")
Signed-off-by: Shawn Guo <shawnguo@kernel.org>