riscv: set default FIT generator script and build target for SPL builds

Now that we have a generic FIT generator script for RISC-V, set it as
the default. To also build the FIT image by default, set the default
build target to "u-boot.itb" if CONFIG_SPL_LOAD_FIT is enabled.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
diff --git a/Kconfig b/Kconfig
index d8e1aa4..1f0904f 100644
--- a/Kconfig
+++ b/Kconfig
@@ -252,7 +252,8 @@
 	default "u-boot-with-spl.sfp" if TARGET_SOCFPGA_GEN5
 	default "u-boot-spl.kwb" if ARCH_MVEBU && SPL
 	default "u-boot-elf.srec" if RCAR_GEN3
-	default "u-boot.itb" if SPL_LOAD_FIT && (ROCKCHIP_RK3399 || ARCH_SUNXI)
+	default "u-boot.itb" if SPL_LOAD_FIT && (ROCKCHIP_RK3399 || \
+				ARCH_SUNXI || RISCV)
 	default "u-boot.kwb" if KIRKWOOD
 	default "u-boot-with-spl.bin" if ARCH_AT91 && SPL_NAND_SUPPORT
 	help
@@ -465,6 +466,7 @@
 	depends on SPL_FIT
 	default "board/sunxi/mksunxi_fit_atf.sh" if SPL_LOAD_FIT && ARCH_SUNXI
 	default "arch/arm/mach-rockchip/make_fit_atf.py" if SPL_LOAD_FIT && ARCH_ROCKCHIP
+	default "arch/riscv/lib/mkimage_fit_opensbi.sh" if SPL_LOAD_FIT && RISCV
 	help
 	  Specifies a (platform specific) script file to generate the FIT
 	  source file used to build the U-Boot FIT image file. This gets