kbuild: LD_VERSION redenomination

Commit ccbef167 ("Kbuild, lto: add ld-version and ld-ifversion
macros") introduced scripts/ld-version.sh for GCC LTO.

At that time, this script handled 5 version fields because GCC LTO
needed the downstream binutils. (https://lkml.org/lkml/2014/4/8/272)

The code snippet from the submitted patch was as follows:

    # We need HJ Lu's Linux binutils because mainline binutils does not
    # support mixing assembler and LTO code in the same ld -r object.
    # XXX check if the gcc plugin ld is the expected one too
    # XXX some Fedora binutils should also support it. How to check for that?
    ifeq ($(call ld-ifversion,-ge,22710001,y),y)
        ...

However, GCC LTO was not merged into the mainline after all.
(https://lkml.org/lkml/2014/4/8/272

)

So, the 4th and 5th fields were never used, and finally removed by
commit 0d61ed17 ("ld-version: Drop the 4th and 5th version
components").

Since then, the last 4-digits returned by this script is always zeros.

Remove the meaningless last 4-digits. This makes the version format
consistent with GCC_VERSION, CLANG_VERSION, LLD_VERSION.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>