[PATCH] ppc64 add gmp-mparam.h

[Roland McGrath]

> Set the WORDSIZE for the GNU multiple precision library (gmp).
> This patch supports both powerpc32 and powerpc64.  The original was
> copied from sysdeps/sparc.  

Since this file is nearly identical on most platforms, I instead just made
the sysdeps/generic version use __WORDSIZE and removed the files for the
platforms that need nothing else (those that don't define IEEE_*).