kontron-sl-mx8mm: fix missing configs and deadlock in CI

Even if board can be successfuly built, CI goes in deadlock (see thread
on https://www.mail-archive.com/u-boot@lists.denx.de/msg419663.html).
This is caused by SYS_CONFIG set in header file and because defconfig
for the board is out of sync with Kconfig. As result, buildman goes on
to read from stdin until an OOM is reached.

Signed-off-by: Stefano Babic <sbabic@denx.de>
CC: Frieder Schrempf <frieder.schrempf@kontron.de>
diff --git a/configs/kontron-sl-mx8mm_defconfig b/configs/kontron-sl-mx8mm_defconfig
index 06c57b7..0289781 100644
--- a/configs/kontron-sl-mx8mm_defconfig
+++ b/configs/kontron-sl-mx8mm_defconfig
@@ -8,6 +8,7 @@
 CONFIG_ENV_SIZE=0x10000
 CONFIG_ENV_OFFSET=0x1f0000
 CONFIG_ENV_SECT_SIZE=0x10000
+CONFIG_SYS_MALLOC_LEN=0x4000000
 CONFIG_DM_GPIO=y
 CONFIG_SPL_DM_SPI=y
 CONFIG_DEFAULT_DEVICE_TREE="imx8mm-kontron-n801x-s"
@@ -17,6 +18,7 @@
 CONFIG_SPL_SERIAL_SUPPORT=y
 CONFIG_BOOTCOUNT_BOOTLIMIT=3
 CONFIG_SPL=y
+CONFIG_SYS_LOAD_ADDR=0x40480000
 CONFIG_SPL_SPI_FLASH_SUPPORT=y
 CONFIG_SPL_SPI_SUPPORT=y
 CONFIG_DISTRO_DEFAULTS=y
@@ -25,7 +27,7 @@
 CONFIG_SPL_LOAD_FIT=y
 # CONFIG_USE_SPL_FIT_GENERATOR is not set
 CONFIG_OF_BOARD_SETUP=y
-CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/kontron/sl-mx8mm/imximage.cfg"
+CONFIG_IMX_CONFIG="board/kontron/sl-mx8mm/imximage.cfg"
 CONFIG_BOARD_TYPES=y
 CONFIG_SPL_BOARD_INIT=y
 CONFIG_SPL_SEPARATE_BSS=y