Update ext/json/generator/depend

Author: hsbt

ext/json/generator/depend

@@ -177,5 +177,6 @@ generator.o: $(hdrdir)/ruby/ruby.h
 generator.o: $(hdrdir)/ruby/st.h
 generator.o: $(hdrdir)/ruby/subst.h
 generator.o: $(srcdir)/../fbuffer/fbuffer.h
+generator.o: $(srcdir)/../vendor/fpconv.c
 generator.o: generator.c
 # AUTOGENERATED DEPENDENCIES END