rockchip: set malloc pool size to 0 before relocation in spl state on rk3036 based board

RK3036 only has 4kb sram, the spl code will use
3.4 ~ 3.5 kb, the last 0.5kb are used for SP and
GD, so there is no space for malloc. Also, the spl
will directly return to bootrom after dram initialized,
they never need the space for malloc.
Signed-off-by: NAndy Yan <andy.yan@rock-chips.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>
Acked-by: NPhilipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: NPhilipp Tomsich <philipp.tomsich@theobroma-systems.com>

configs/evb-rk3036_defconfig

@@ -4,6 +4,7 @@ CONFIG_ROCKCHIP_RK3036=y
 CONFIG_TARGET_EVB_RK3036=y
 CONFIG_SPL_STACK_R_ADDR=0x80000
 CONFIG_DEFAULT_DEVICE_TREE="rk3036-sdk"
+CONFIG_SPL_SYS_MALLOC_F_LEN=0x0
 CONFIG_DEBUG_UART=y
 CONFIG_ENV_IS_NOWHERE=y
 # CONFIG_DISPLAY_CPUINFO is not set

configs/kylin-rk3036_defconfig

@@ -5,6 +5,7 @@ CONFIG_TARGET_KYLIN_RK3036=y
 CONFIG_SPL_STACK_R_ADDR=0x80000
 CONFIG_DEFAULT_DEVICE_TREE="rk3036-sdk"
 CONFIG_ENV_IS_IN_MMC=y
+CONFIG_SPL_SYS_MALLOC_F_LEN=0x0
 # CONFIG_DISPLAY_CPUINFO is not set
 CONFIG_SPL_STACK_R=y
 # CONFIG_CMD_IMLS is not set