8208463: jdk.internal.vm.compiler's module-info.java.extra contains duplicated provides of the same service interface

Reviewed-by: mchung

make/gensrc/Gensrc-jdk.internal.vm.compiler.gmk

@@ -124,7 +124,7 @@ $(GENSRC_DIR)/module-info.java.extra: $(GENSRC_DIR)/_gensrc_proc_done
 	($(CD) $(GENSRC_DIR)/META-INF/providers && \
 	    p=""; \
 	    impl=""; \
-	    for i in $$($(LS) | $(SORT)); do \
+	    for i in $$($(GREP) '^' * | $(SORT) -t ':' -k 2 | $(SED) 's/:.*//'); do \
 	      c=$$($(CAT) $$i | $(TR) -d '\n\r'); \
 	      if test x$$p != x$$c; then \
                 if test x$$p != x; then \