.vmlinux.objs is used by modpost, so scripts/Makefile.modpost is
a better place to generate it.

It is used only when CONFIG_MODVERSIONS=y. It should be guarded
by "ifdef CONFIG_MODVERSIONS".
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Tested-by: NNick Desaulniers <ndesaulniers@google.com>
Reviewed-by: NNicolas Schier <nicolas@fjasle.eu>