Revert "Makefile: Drop SPL_FIT_GENERATOR / SPL_FIT_SOURCE support" changes

:hile we had hoped to be able to remove these options finally, it was
missed that zynq still requires these currently.

This reverts commit 5b9261fb0b1ed087387f2036d279fd3f4bb20a61 and
commit 099b6df556c95f5d06864612e9199eab7ba50ed3.

Reported-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/Makefile b/Makefile
index 0005e99..3267fb1 100644
--- a/Makefile
+++ b/Makefile
@@ -1146,6 +1146,13 @@
 	@echo >&2 "See doc/develop/devicetree/control.rst for more info."
 	@echo >&2 "===================================================="
 endif
+ifneq ($(CONFIG_SPL_FIT_GENERATOR),)
+	@echo >&2 "===================== WARNING ======================"
+	@echo >&2 "This board uses CONFIG_SPL_FIT_GENERATOR. Please migrate"
+	@echo >&2 "to binman instead, to avoid the proliferation of"
+	@echo >&2 "arch-specific scripts with no tests."
+	@echo >&2 "===================================================="
+endif
 	$(call deprecated,CONFIG_WDT,DM watchdog,v2019.10,\
 		$(CONFIG_WATCHDOG)$(CONFIG_HW_WATCHDOG))
 	$(call deprecated,CONFIG_DM_I2C,I2C drivers,v2022.04,$(CONFIG_SYS_I2C_LEGACY))
@@ -1412,6 +1419,23 @@
 u-boot.ldr.hex u-boot.ldr.srec: u-boot.ldr FORCE
 	$(call if_changed,objcopy)
 
+# Boards with more complex image requirements can provide an .its source file
+# or a generator script
+# NOTE: Please do not use this. We are migrating away from Makefile rules to use
+# binman instead.
+ifneq ($(CONFIG_SPL_FIT_SOURCE),"")
+U_BOOT_ITS := u-boot.its
+$(U_BOOT_ITS): $(subst ",,$(CONFIG_SPL_FIT_SOURCE))
+	$(call if_changed,copy)
+else
+ifneq ($(CONFIG_USE_SPL_FIT_GENERATOR),)
+U_BOOT_ITS := u-boot.its
+$(U_BOOT_ITS): $(U_BOOT_ITS_DEPS) FORCE
+	$(srctree)/$(CONFIG_SPL_FIT_GENERATOR) \
+	$(patsubst %,$(dt_dir)/%.dtb,$(subst ",,$(CONFIG_OF_LIST))) > $@
+endif
+endif
+
 ifdef CONFIG_SPL_LOAD_FIT
 MKIMAGEFLAGS_u-boot.img = -f auto -A $(ARCH) -T firmware -C none -O u-boot \
 	-a $(CONFIG_TEXT_BASE) -e $(CONFIG_SYS_UBOOT_START) \