Convert CONFIG_SYS_SPL_MALLOC_SIZE et al to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_SPL_MALLOC_SIZE
   CONFIG_SYS_SPL_MALLOC_START

We introduce a default value here as well, and CONFIG_SYS_SPL_MALLOC to
control if we have a malloc pool or not.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/xilinx_zynqmp_mini_emmc0_defconfig b/configs/xilinx_zynqmp_mini_emmc0_defconfig
index 131dfc0..a248cbf 100644
--- a/configs/xilinx_zynqmp_mini_emmc0_defconfig
+++ b/configs/xilinx_zynqmp_mini_emmc0_defconfig
@@ -30,6 +30,10 @@
 CONFIG_SPL_BSS_MAX_SIZE=0x80000
 # CONFIG_SPL_SHARES_INIT_SP_ADDR is not set
 CONFIG_SPL_STACK=0xfffffffc
+CONFIG_SYS_SPL_MALLOC=y
+CONFIG_HAS_CUSTOM_SPL_MALLOC_START=y
+CONFIG_CUSTOM_SYS_SPL_MALLOC_ADDR=0x20000000
+CONFIG_SYS_SPL_MALLOC_SIZE=0x1000000
 # CONFIG_CMDLINE_EDITING is not set
 # CONFIG_AUTO_COMPLETE is not set
 CONFIG_SYS_MAXARGS=64