Changes to ghc(3)

Changes to ghc:
commit 214ad2d24cda4aaef541df3e213d5c4845f95c71
Author: Peter Trommler <ptrommler@scm.org>
Date:   Wed Apr 30 11:41:51 2014 +0200

    Fix globalRegMaybe for unregisterised build.

    In commit 83a003f globalRegMaybe will be called but panics
    for unregisterised compilers.

    In an unregisterised compiler there are no global registers
    so always return `Nothing`.

    Fixes #9055.

commit 21f17d06aa5c33e639f1b0d37b4bf888b494c441
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date:   Tue May 13 13:17:19 2014 +0100

    Fix invariant in mkAppCoFlexible

    mkAppCoFlexible was breaking the invariant that the head of a TyConAppCo cannot
    be a type synonym.  This small patch fixes it.

commit 4cfc1fae11ec9a5c4b34ac747f0ce50f52423eba
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date:   Tue May 13 13:15:45 2014 +0100

    Lint should check that TyConAppCo doesn't have a synonym in the tycon position

    That is why Lint didn't nail Trac #9102