Expose GHCI_TABLES_NEXT_TO_CODE in some header file

[nomeata]

Projects that are “close” to the GHC Heap need to know the value of GHCI_TABLES_NEXT_TO_CODE; currently they are just guessing (e.g.  http://hackage.haskell.org/packages/archive/vacuum/1.0.0.2/doc/html/src/GHC-Vacuum-Internal.html). It would be nice if this would be exported as a macro in, e.g. GHCConstants.h.

[marlowsd@…]

commit 5513fe060a82a9a3ca1d4cff22947faafc538cfe

Author: Simon Marlow <marlowsd@gmail.com>
Date:   Tue Mar 13 09:26:41 2012 +0000

    define TABLES_NEXT_TO_CODE in ghcautoconf.h (#5933)

 includes/ghc.mk |   31 +++++++++++++++++--------------
 1 files changed, 17 insertions(+), 14 deletions(-)