kbuild: remove duplicated dependency between modules and modules_check

The dependency, "modules: modules_check" is specified twice.
Commit 1a998be ("kbuild: check module name conflict for external
modules as well") missed to clean it up.

'PHONY += modules' also appears twice.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Makefile

@@ -1431,8 +1431,7 @@ endif
 # Build modules
 #
 
-PHONY += modules
-modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
+modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_prepare
 
 cmd_modules_order = cat $(real-prereqs) > $@