11394 iconv_modules build could be much more parallel

@@ -37,9 +37,11 @@
 
 .KEEP_STATE:
 
 all clean clobber install lint echo: $(SUBDIRS)
 
+.PARALLEL: $(SUBDIRS)
+
 $(SUBDIRS): FRC
         @cd $@; pwd; $(MAKE) $(TARGET)
 
 FRC: