fix(imx8m): correct the rank info get fro mstr

the bitfield of active_ranks in MSTR is defined as below.
Correct the rank num get in dram_info.

  0x01: one rank;
  0x11: two rank;

Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Anson Huang <anson.huang@nxp.com>
Change-Id: Idcadb39f492a8fe81c973ac4136d9a1eaa32f54b
2 files changed