rockchip: rk3368: use defaule value for SYS_MALLOC_F_LEN

There is no difference in rk3368 board use for SYS_MALLOC_F_LEN,
so we can use default value.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/mach-rockchip/rk3368/Kconfig b/arch/arm/mach-rockchip/rk3368/Kconfig
index 141d2f6..2220f59 100644
--- a/arch/arm/mach-rockchip/rk3368/Kconfig
+++ b/arch/arm/mach-rockchip/rk3368/Kconfig
@@ -48,6 +48,9 @@
 config SYS_SOC
 	default "rk3368"
 
+config SYS_MALLOC_F_LEN
+	default 0x2000
+
 source "board/theobroma-systems/lion_rk3368/Kconfig"
 source "board/rockchip/sheep_rk3368/Kconfig"
 source "board/geekbuying/geekbox/Kconfig"
diff --git a/configs/evb-px5_defconfig b/configs/evb-px5_defconfig
index 9601b12..6945e68 100644
--- a/configs/evb-px5_defconfig
+++ b/configs/evb-px5_defconfig
@@ -3,7 +3,6 @@
 CONFIG_SYS_TEXT_BASE=0x00200000
 CONFIG_SPL_LIBCOMMON_SUPPORT=y
 CONFIG_SPL_LIBGENERIC_SUPPORT=y
-CONFIG_SYS_MALLOC_F_LEN=0x2000
 CONFIG_ROCKCHIP_RK3368=y
 CONFIG_TPL_LDSCRIPT="arch/arm/mach-rockchip/u-boot-tpl-v8.lds"
 CONFIG_ROCKCHIP_SPL_RESERVE_IRAM=0x40000
diff --git a/configs/lion-rk3368_defconfig b/configs/lion-rk3368_defconfig
index 75e8583..ef05ba5 100644
--- a/configs/lion-rk3368_defconfig
+++ b/configs/lion-rk3368_defconfig
@@ -3,7 +3,6 @@
 CONFIG_SYS_TEXT_BASE=0x00200000
 CONFIG_SPL_LIBCOMMON_SUPPORT=y
 CONFIG_SPL_LIBGENERIC_SUPPORT=y
-CONFIG_SYS_MALLOC_F_LEN=0x2000
 CONFIG_ROCKCHIP_RK3368=y
 CONFIG_ROCKCHIP_SPL_RESERVE_IRAM=0x0
 CONFIG_TPL_LIBCOMMON_SUPPORT=y
diff --git a/configs/sheep-rk3368_defconfig b/configs/sheep-rk3368_defconfig
index cff1905..4883f59 100644
--- a/configs/sheep-rk3368_defconfig
+++ b/configs/sheep-rk3368_defconfig
@@ -1,7 +1,6 @@
 CONFIG_ARM=y
 CONFIG_ARCH_ROCKCHIP=y
 CONFIG_SYS_TEXT_BASE=0x00200000
-CONFIG_SYS_MALLOC_F_LEN=0x1000
 CONFIG_ROCKCHIP_RK3368=y
 CONFIG_TARGET_SHEEP=y
 CONFIG_NR_DRAM_BANKS=1