modpost: pass -N option only for modules modpost

The built-in only code is not required to have MODULE_IMPORT_NS() to
use symbols. So, the namespace is not checked for vmlinux(.o).

Do not pass the meaningless -N option to the first pass of modpost.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

scripts/Makefile.modpost

@@ -53,7 +53,6 @@ MODPOST = scripts/mod/modpost								\
 	$(if $(KBUILD_EXTMOD),$(addprefix -e ,$(KBUILD_EXTRA_SYMBOLS)))			\
 	$(if $(KBUILD_EXTMOD),-o $(modulesymfile))					\
 	$(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E)					\
-	$(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N) 	\
 	$(if $(KBUILD_MODPOST_WARN),-w)
 
 ifdef MODPOST_VMLINUX
@@ -82,6 +81,10 @@ include $(if $(wildcard $(KBUILD_EXTMOD)/Kbuild), \
              $(KBUILD_EXTMOD)/Kbuild, $(KBUILD_EXTMOD)/Makefile)
 endif
 
+# modpost options for modules (both in-kernel and external)
+MODPOST += \
+	$(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N)
+
 # 'make -i -k' ignores compile errors, and builds as many modules as possible.
 ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),)
 MODPOST += -n