kbuild: remove unnecessary $(subst $(obj)/, , ...) in modname-multi

In the context ...

    $(obj)/%.s: $(src)/%.c FORCE
            $(call if_changed_dep,cc_s_c)

    $(obj)/%.i: $(src)/%.c FORCE
            $(call if_changed_dep,cpp_i_c)

    $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
            $(call cmd,force_checksrc)
            $(call if_changed_rule,cc_o_c)

    $(obj)/%.lst: $(src)/%.c FORCE
            $(call if_changed_dep,cc_lst_c)

'$*' returns the stem of the target (the part of '%'), so $(obj)/ has
already been ripped off.

$(subst $(obj)/,,$*.o) is the same as $*.o

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Cao jin <caoj.fnst@cn.fujitsu.com>

scripts/Makefile.lib

@@ -175,7 +175,7 @@ dtc_cpp_flags  = -Wp,-MD,$(depfile).pre.tmp -nostdinc                    \
 
 # Finds the multi-part object the current object will be linked into
 modname-multi = $(sort $(foreach m,$(multi-used),\
-		$(if $(filter $(subst $(obj)/,,$*.o), $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=))))
+		$(if $(filter $*.o, $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=))))
 
 # Useful for describing the dependency of composite objects
 # Usage: