kbuild: remove deprecated host-progs variable

The host-progs has been kept as an alias of hostprogs-y for a long time
(at least since the beginning of Git era), with the clear prompt:
  Usage of host-progs is deprecated. Please replace with hostprogs-y!

Enough time for the migration has passed.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>

arch/xtensa/boot/Makefile

@@ -30,8 +30,7 @@ Image: boot-elf
 zImage: boot-redboot
 uImage: $(obj)/uImage
 
-boot-elf boot-redboot: $(addprefix $(obj)/,$(subdir-y)) \
-		       $(addprefix $(obj)/,$(host-progs))
+boot-elf boot-redboot: $(addprefix $(obj)/,$(subdir-y))
 	$(Q)$(MAKE) $(build)=$(obj)/$@ $(MAKECMDGOALS)
 
 OBJCOPYFLAGS = --strip-all -R .comment -R .note.gnu.build-id -O binary

scripts/Makefile.build

@@ -53,13 +53,6 @@ endif
 
 include scripts/Makefile.lib
 
-ifdef host-progs
-ifneq ($(hostprogs-y),$(host-progs))
-$(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
-hostprogs-y += $(host-progs)
-endif
-endif
-
 # Do not include host rules unless needed
 ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
 include scripts/Makefile.host

scripts/Makefile.clean

@@ -38,7 +38,6 @@ subdir-ymn	:= $(addprefix $(obj)/,$(subdir-ymn))
 
 __clean-files	:= $(extra-y) $(extra-m) $(extra-)       \
 		   $(always) $(targets) $(clean-files)   \
-		   $(host-progs)                         \
 		   $(hostprogs-y) $(hostprogs-m) $(hostprogs-) \
 		   $(hostlibs-y) $(hostlibs-m) $(hostlibs-) \
 		   $(hostcxxlibs-y) $(hostcxxlibs-m)