kbuild: always create intermediate vmlinux.unstripped

kbuild: always create intermediate vmlinux.unstripped

Generate the intermediate vmlinux.unstripped regardless of
CONFIG_ARCH_VMLINUX_NEEDS_RELOCS.

If CONFIG_ARCH_VMLINUX_NEEDS_RELOCS is unset, vmlinux.unstripped and
vmlinux are identiacal.

This simplifies the build rule, and allows to strip more sections
by adding them to remove-section-y.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Link: https://patch.msgid.link/a48ca543fa2305bd17324f41606dcaed9b19f2d4.1758182101.git.legion@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>