Fix PR458: * Don't include Makefile.rules in set of preconditions, it never has to be   copied to objdir. * Enable the "update makefile first before executing targets" feature in   gnu make by *not* using a full path to the Makefile in the rule.
Fix PR458:
* Don't include Makefile.rules in set of preconditions, it never has to be
  copied to objdir.
* Enable the "update makefile first before executing targets" feature in
  gnu make by *not* using a full path to the Makefile in the rule.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@17920 91177308-0d34-0410-b5e6-96231b3b80d8

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