kbuild: Allow external modules to use host-progs with no warning

Only warn if $(host-progs) and $(hostptogs-y) are not equal.
This allows external modules to use:
hostprogs-y := file ...
host-progs  := $(hostprogs-y)

This is backwards compatible and will not warn.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

scripts/Makefile.build

@@ -15,9 +15,11 @@ include $(obj)/Makefile
 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 unles needed
 ifneq ($(hostprogs-y)$(hostprogs-m),)