redundant gkey and key2tval in ltable.h (5.2.0-work3)

[David Manura <dm.lua@...>]

Lua 5.1.4 ltable.h contains this:

  #define gkey(n)       (&(n)->i_key.nk)
  #define key2tval(n)  (&(n)->i_key.tvk)

Lua 5.2.0-work3 makes them identical:

  #define gkey(n)      (&(n)->i_key.tvk)
  #define key2tval(n) (&(n)->i_key.tvk)

nk (anonymous struct) and tvk (TValue) differ only in type because
they are members of the same union.  Any reason not to eliminate
key2tval(n) ?


(FYI, here's a description of this area of code:
http://lua-users.org/lists/lua-l/2008-06/msg00298.html .)