riscv: Drop USE_SPL_FIT_GENERATOR

Now that we have switched to binman to generate u-boot.itb for all
RISC-V boards, USE_SPL_FIT_GENERATOR is no longer needed and can
be dropped.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/common/Kconfig.boot b/common/Kconfig.boot
index 71a215c..3c6e77d 100644
--- a/common/Kconfig.boot
+++ b/common/Kconfig.boot
@@ -274,14 +274,13 @@
 
 config USE_SPL_FIT_GENERATOR
 	bool "Use a script to generate the .its script"
-	default y if SPL_FIT && !ARCH_SUNXI
+	default y if SPL_FIT && (!ARCH_SUNXI && !RISCV)
 
 config SPL_FIT_GENERATOR
 	string ".its file generator script for U-Boot FIT image"
 	depends on USE_SPL_FIT_GENERATOR
 	default "arch/arm/mach-rockchip/make_fit_atf.py" if SPL_LOAD_FIT && ARCH_ROCKCHIP
 	default "arch/arm/mach-zynqmp/mkimage_fit_atf.sh" if SPL_LOAD_FIT && ARCH_ZYNQMP
-	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