ARM: at91: Switch sama5d2_icp_mmc to simple malloc in SPL

To avoid SRAM overflow in the SPL build, use simple malloc implementation.

Signed-off-by: Marek Vasut <marex@denx.de>
diff --git a/configs/sama5d2_icp_mmc_defconfig b/configs/sama5d2_icp_mmc_defconfig
index 6b7e308..185694d 100644
--- a/configs/sama5d2_icp_mmc_defconfig
+++ b/configs/sama5d2_icp_mmc_defconfig
@@ -41,6 +41,7 @@
 CONFIG_SPL_HAS_BSS_LINKER_SECTION=y
 CONFIG_SPL_BSS_START_ADDR=0x20000000
 CONFIG_SPL_BSS_MAX_SIZE=0x80000
+CONFIG_SPL_SYS_MALLOC_SIMPLE=y
 # CONFIG_SPL_SHARES_INIT_SP_ADDR is not set
 CONFIG_SYS_SPL_MALLOC=y
 CONFIG_SYS_SPL_MALLOC_SIZE=0x80000