kbuild: replace $(linked-object) with CONFIG options

*.prelink.o is created when CONFIG_LTO_CLANG or CONFIG_X86_KERNEL_IBT
is enabled.

Replace $(linked-object) with $(CONFIG_LTO_CLANG)$(CONFIG_X86_KERNEL_IBT)
so you will get a quick idea of when the --link option is passed.

No functional change is intended.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14

scripts/Makefile.build

@@ -219,7 +219,7 @@ objtool_args =								\
 	$(if $(CONFIG_STACK_VALIDATION), --stackval)			\
 	$(if $(CONFIG_HAVE_STATIC_CALL_INLINE), --static-call)		\
 	--uaccess							\
-	$(if $(linked-object), --link)					\
+	$(if $($(CONFIG_LTO_CLANG)$(CONFIG_X86_KERNEL_IBT)), --link)	\
 	$(if $(part-of-module), --module)				\
 	$(if $(CONFIG_GCOV_KERNEL), --no-unreachable)
 
@@ -284,7 +284,6 @@ quiet_cmd_cc_prelink_modules = LD [M]  $@
 # modules into native code
 $(obj)/%.prelink.o: objtool-enabled = y
 $(obj)/%.prelink.o: part-of-module := y
-$(obj)/%.prelink.o: linked-object := y
 
 $(obj)/%.prelink.o: $(obj)/%.o FORCE
 	$(call if_changed,cc_prelink_modules)