dm: mx6: Adjust mx6sxsabresd to use Kconfig for DM_THERMAL

Use Kconfig instead of board config for DM and DM_THERMAL.
Signed-off-by: NSimon Glass <sjg@chromium.org>

configs/mx6sxsabresd_defconfig

@@ -3,3 +3,5 @@ CONFIG_ARM=y
 CONFIG_TARGET_MX6SXSABRESD=y
 CONFIG_SYS_MALLOC_F=y
 CONFIG_SYS_MALLOC_F_LEN=0x400
+CONFIG_DM=y
+CONFIG_DM_THERMAL=y

configs/mx6sxsabresd_spl_defconfig

@@ -2,3 +2,5 @@ CONFIG_SPL=y
 CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=arch/arm/imx-common/spl_sd.cfg,MX6SX"
 +S:CONFIG_ARM=y
 +S:CONFIG_TARGET_MX6SXSABRESD=y
+CONFIG_DM=y
+CONFIG_DM_THERMAL=y

include/configs/mx6sxsabresd.h

@@ -227,8 +227,6 @@
 #define CONFIG_PCIE_IMX_POWER_GPIO	IMX_GPIO_NR(2, 1)
 #endif
 
-#define CONFIG_DM
-#define CONFIG_DM_THERMAL
 #define CONFIG_IMX6_THERMAL
 
 #define CONFIG_CMD_FUSE