kbuild: kill backward compatibility checks
These checks has been present for several kernel releases (> 5).
So lets just get rid of them.
With this we no longer check for use of:
EXTRA_TARGETS, O_TARGET, L_TARGET, list-multi, export-objs
There were three remaining in-tree users of O_TARGET in some
unmaintained sh64 code - mail sent to the maintainer + list.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean
index cff3349..2c64710 100644
--- a/scripts/Makefile.clean
+++ b/scripts/Makefile.clean
@@ -40,7 +40,7 @@
# build a list of files to remove, usually releative to the current
# directory
-__clean-files := $(extra-y) $(EXTRA_TARGETS) $(always) \
+__clean-files := $(extra-y) $(always) \
$(targets) $(clean-files) \
$(host-progs) \
$(hostprogs-y) $(hostprogs-m) $(hostprogs-)