kbuild: move archive command to scripts/Makefile.lib

scripts/Makefile.build and arch/s390/boot/Makefile use the same
command (thin archiving with symbol table creation).

Avoid the code duplication, and move it to scripts/Makefile.lib.

Signed-off-by: Masahiro Yamada <[e-mail]>

arch/s390/boot/Makefile

···
 $(obj)/compressed/vmlinux: $(obj)/startup.a FORCE
 	$(Q)$(MAKE) $(build)=$(obj)/compressed $@
 
-quiet_cmd_ar = AR      $@
-      cmd_ar = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(real-prereqs)
-
 $(obj)/startup.a: $(OBJECTS) FORCE
 	$(call if_changed,ar)
 

scripts/Makefile.build

···
 # Rule to compile a set of .o files into one .a file (with symbol table)
 #
 ifdef lib-target
-quiet_cmd_link_l_target = AR      $@
-
-# lib target archives do get a symbol table and index
-cmd_link_l_target = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(real-prereqs)
 
 $(lib-target): $(lib-y) FORCE
-	$(call if_changed,link_l_target)
+	$(call if_changed,ar)
 
 targets += $(lib-target)
 

scripts/Makefile.lib

···
 quiet_cmd_ld = LD      $@
       cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
 
+# Archive
+# ---------------------------------------------------------------------------
+
+quiet_cmd_ar = AR      $@
+      cmd_ar = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(real-prereqs)
+
 # Objcopy
 # ---------------------------------------------------------------------------