patch applied (ghc): Check dblatex actually creates the files we tell it to

[Ian Lynagh]

Sun May 30 10:10:43 PDT 2010  Ian Lynagh <igloo at earth.li>
  * Check dblatex actually creates the files we tell it to
  If it fails, it still exits successfully.

    M ./rules/docbook.mk +2

View patch online:
http://darcs.haskell.org/cgi-bin/darcsweb.cgi?r=ghc;a=darcs_commitdiff;h=20100530171043-3fd76-988e413acc65c7cc27fb4830ca9a2c0dcb457c2f.gz