Revert "Makefile: install modules.builtin even if CONFIG_MODULES=n"

This reverts commit e0b250b57d,
which broke build systems that need to install files to a certain
path, but do not set INSTALL_MOD_PATH when invoking 'make install'.

  $ make INSTALL_PATH=/tmp/destdir install
  mkdir: cannot create directory ‘/lib/modules/5.8.0-rc1+/’: Permission denied
  Makefile:1342: recipe for target '_builtin_inst_' failed
  make: *** [_builtin_inst_] Error 1

While modules.builtin is useful also for CONFIG_MODULES=n, this change
in the behavior is quite unexpected. Maybe "make modules_install"
can install modules.builtin irrespective of CONFIG_MODULES as Jonas
originally suggested.

Anyway, that commit should be reverted ASAP.

Reported-by: Douglas Anderson <dianders@chromium.org>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>

Makefile

@@ -1336,16 +1336,6 @@ dt_binding_check: scripts_dtc
 # ---------------------------------------------------------------------------
 # Modules
 
-# install modules.builtin regardless of CONFIG_MODULES
-PHONY += _builtin_inst_
-_builtin_inst_:
-	@mkdir -p $(MODLIB)/
-	@cp -f modules.builtin $(MODLIB)/
-	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
-
-PHONY += install
-install: _builtin_inst_
-
 ifdef CONFIG_MODULES
 
 # By default, build modules as well
@@ -1389,7 +1379,7 @@ PHONY += modules_install
 modules_install: _modinst_ _modinst_post
 
 PHONY += _modinst_
-_modinst_: _builtin_inst_
+_modinst_:
 	@rm -rf $(MODLIB)/kernel
 	@rm -f $(MODLIB)/source
 	@mkdir -p $(MODLIB)/kernel
@@ -1399,6 +1389,8 @@ _modinst_: _builtin_inst_
 		ln -s $(CURDIR) $(MODLIB)/build ; \
 	fi
 	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
+	@cp -f modules.builtin $(MODLIB)/
+	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
 
 # This depmod is only for convenience to give the initial