[GHC] #12623: Make Harbormaster less terrible in the face of submodule updates

[GHC]

#12623: Make Harbormaster less terrible in the face of submodule updates
-------------------------------------+-------------------------------------
           Reporter:  bgamari        |             Owner:  bgamarii
               Type:  task           |            Status:  new
           Priority:  highest        |         Milestone:
          Component:  Compiler       |           Version:  8.0.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 Currently submodule updates appear to break Harbormaster builds. This is
 bad. Fix it.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12623>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler