kbuild: use scripts/Makefile.clean
This commit refactors cleaning targets such as
clean, clobber, mrpropper, distclean
with scripts/Makefile.clean.
By using scripts/Makefile.clean, we can recursively descend
into subdirectories and delete generated files there.
We do not need add a big list of generated files
to the "clean" target.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/scripts/Makefile b/scripts/Makefile
new file mode 100644
index 0000000..ebbadc9
--- /dev/null
+++ b/scripts/Makefile
@@ -0,0 +1,2 @@
+# Let clean descend into subdirs
+subdir- += basic