Improving GMP configure

[Torbjorn Granlund]

nisse at lysator.liu.se (Niels Möller) writes:

  >    o Deprecate none-*-* and add an option --disable-assembly.
  
  Makes sense to me. The nettle configure script calls that option
  "--disable-assembler"; I don't know English well enough to say which
  name is best, but some consitency would be nice. Any other (GNU)
  packages that have a configure option liek that?
  
A search for "assembly code" and "assembler code" voted 2:1 for the
former.  I put in --disable-assembly for now, feel free to add a
compatibility option with 'assembler'.  I semi-kept the none target, but
it now only prints an error message with advice about the new option.

Things are pushed into the main repo.

(I take the term "assembler code" as code to feed to the assembler, the
latter being a program.)

-- 
Torbjörn