stable inclusion
from stable-v5.10.141
commit ad697ade5939b5a40eb65b557083d083cf129790
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I685FC

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ad697ade5939b5a40eb65b557083d083cf129790

--------------------------------

commit 23a0cb8e upstream.

When building an external module, if users don't need to separate the
compilation output and source code, they run the following command:
"make -C $(LINUX_SRC_DIR) M=$(PWD)". At this point, "$(KBUILD_EXTMOD)"
and "$(src)" are the same.

If they need to separate them, they run "make -C $(KERNEL_SRC_DIR)
O=$(KERNEL_OUT_DIR) M=$(OUT_DIR) src=$(PWD)". Before running the
command, they need to copy "Kbuild" or "Makefile" to "$(OUT_DIR)" to
prevent compilation failure.

So the kernel should change the included path to avoid the copy operation.
Signed-off-by: NJing Leng <jleng@ambarella.com>
[masahiro: I do not think "M=$(OUT_DIR) src=$(PWD)" is the official way,
but this patch is a nice clean up anyway.]
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Signed-off-by: NNicolas Schier <n.schier@avm.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NJialin Zhang <zhangjialin11@huawei.com>
Reviewed-by: NZheng Zengkai <zhengzengkai@huawei.com>
(cherry picked from commit 667ba256)