dts: emmc: uboot enable emmc config [2/3]

PD#SWPL-736

Problem:
The s400 emmc platform uboot cannot be loaded
into kernel normally

Solution:
enable enable emmc node in dtb by fdt command.
    and modify malloc max size to 18M.

Verify:
s400

Change-Id: Iaef58f1b05a952793d414eb82ac476d88d910fe1
Signed-off-by: yuegui.he <yuegui.he@amlogic.com>

MAINTAINERS

@@ -14677,3 +14677,9 @@ AMLOGIC VDIN DRIVERS
 M:	Xuhua Zhang <xuhua.zhang@amlogic.com>
 F:	drivers/amlogic/media/vin/tvin/vdin/vdin_afbce.c
 F:	drivers/amlogic/media/vin/tvin/vdin/vdin_afbce.h
+
+AMLOGIC MESONAXG S400 DTS
+M:	Yuegui He <yuegui.he@amlogic.com>
+F:	arch/arm64/boot/dts/amlogic/axg_s400_v03.dts
+F:	arch/arm64/boot/dts/amlogic/axg_s400emmc.dts
+F:	arch/arm64/boot/dts/amlogic/axg_s400emmc_v03.dts

arch/arm64/boot/dts/amlogic/axg_s400_v03.dts

@@ -663,6 +663,7 @@
 			f_max = <200000000>;
 			max_req_size = <0x20000>; /**128KB*/
 			gpio_dat3 = <&gpio BOOT_3 GPIO_ACTIVE_HIGH>;
+			tx_delay = <4>;
 			hw_reset = <&gpio BOOT_9 GPIO_ACTIVE_HIGH>;
 			card_type = <1>;
 			/* 1:mmc card(include eMMC),