[commit: ghc] ghc-8.4: Update Cabal submodule (61db0b8)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/61db0b8941cfb7ed8941ed29bdb04bd8ef3b71a5/ghc

>---------------------------------------------------------------

commit 61db0b8941cfb7ed8941ed29bdb04bd8ef3b71a5
Author: Oleg Grenrus <oleg.grenrus at iki.fi>
Date:   Sun Jan 21 20:37:17 2018 +0200

    Update Cabal submodule
    
    - Cabal-2.2 uses SPDX license identifiers, so I had to update
      `cabal-version: 2.1` packages `license: BSD3` to
      `license: BSD-3-Clause`
    - `ghc-cabal` used old ReadP parsec, now it uses `parsec` too
    - InstalledPackageInfo pretty-printing have changed a little,
      fields with default values aren't printed. This can be changed in
      `Cabal` still, but I haven't found problems with omitting them.
    
    Note: `BSD-3-Clause` is parsed as "name = BSD, version = 3" by old
    parser (because 3-Clause looks like version 3 with tag Clause).
    If you see *"BSD-3" is not a valid license*, then something is using
    old parser still.
    
    Fixes #9885.
    
    (cherry picked from commit 5d6e0806c690ac1958e4cbf609bc6b18048fb761)


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61db0b8941cfb7ed8941ed29bdb04bd8ef3b71a5
 libraries/Cabal                                    |  2 +-
 libraries/base/base.cabal                          |  2 +-
 libraries/ghc-prim/ghc-prim.cabal                  |  2 +-
 .../backpack/cabal/bkpcabal06/bkpcabal06.cabal     |  2 +-
 testsuite/tests/cabal/ghcpkg01.stdout              | 39 ++++------------------
 utils/ghc-cabal/Main.hs                            |  6 ++--
 6 files changed, 13 insertions(+), 40 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 61db0b8941cfb7ed8941ed29bdb04bd8ef3b71a5