FROMGIT: kbuild: read *.mod to get objects passed to $(LD) or $(AR)

ld and ar support @file, which command-line options are read from.

Now that *.mod lists the member objects in the correct order, without
duplication, it is ready to be passed to ld and ar.

By using the @file syntax, people will not be worried about the pitfall
described in the NOTE.

Bug: 175420575
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
(cherry picked from commit 9170b27757d21460755254045bad4933cb631776
 https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git

 kbuild)
[eberman: Fix conflicts with commit 557054dd]
Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
Change-Id: Id5bbd99ce940dc5eb40e2f9e75182a50a2eeff47