ARM: imx: Add 2 GiB DRAM support for DH electronics i.MX8M Plus DHCOM

The DH electronics i.MX8M Plus DHCOM SoM currently supports only 4 GiB
of DRAM population option. Add another population option with 2 GiB of
DRAM. The chips used on the 2 GiB option are 2x K4F6E3S4HM-MGCJ .

Signed-off-by: Marek Vasut <marex@denx.de>
diff --git a/board/dhelectronics/dh_imx8mp/spl.c b/board/dhelectronics/dh_imx8mp/spl.c
index 95de745..e2aa874 100644
--- a/board/dhelectronics/dh_imx8mp/spl.c
+++ b/board/dhelectronics/dh_imx8mp/spl.c
@@ -99,7 +99,7 @@
 	NULL,					/* 512 MiB */
 	NULL,					/* 1024 MiB */
 	NULL,					/* 1536 MiB */
-	NULL,					/* 2048 MiB */
+	&dh_imx8mp_dhcom_dram_timing_16g_x32,	/* 2048 MiB */
 	NULL,					/* 3072 MiB */
 	&dh_imx8mp_dhcom_dram_timing_32g_x32,	/* 4096 MiB */
 	NULL,					/* 6144 MiB */