arm: am57xx: cl-som-am57x: support for FS boot

Supported boot devices are raw QSPI and raw SD card.
Add support for a FAT16/32 file system for SD card.

The SOC's boot ROM only supports FAT file system.
Therefore remove the SPL support for the EXT file system.

Signed-off-by: Uri Mashiach <uri.mashiach@compulab.co.il>
Reviewed-by: Tom Rini <trini@konsulko.com>

configs/cl-som-am57x_defconfig

@@ -5,6 +5,7 @@ CONFIG_TARGET_CL_SOM_AM57X=y
 # CONFIG_SPL_NAND_SUPPORT is not set
 CONFIG_VERSION_VARIABLE=y
 CONFIG_SPL=y
+# CONFIG_SPL_EXT_SUPPORT is not set
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_BOOTZ=y
 # CONFIG_CMD_IMLS is not set

include/configs/cl-som-am57x.h

@@ -42,9 +42,9 @@
 #define CONFIG_SPL_SPI_FLASH_SUPPORT
 #define CONFIG_SPL_SPI_LOAD
 
-/* SD/MMC RAW boot */
-#undef CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
-#undef CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
+/* SD/MMC RAW/FS boot */
+#define CONFIG_SPL_FS_LOAD_PAYLOAD_NAME "u-boot.img"
+#define CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 1
 
 /* Environment */
 #define CONFIG_ENV_SIZE			(16 << 10) /* 16 KiB env size */