describe NetBSD, rather than 386BSD 0.1.
Removed 386BSD and BDE control word constants, since we don't need and
will never use them. However, The iBCS control word constant is kept,
since we might want to use it in the iBCS binary compatibility code.
so I've changed it to 0x127f. 64 bit precision causes errors in paranoia
and our math library, changing to 53 bit precision solves these problems.
I've been told that long double support in Gcc 2.5 requires 64 bit mode,
so a comprehensive FP strategy (compiler, library, FPU, emulator) will
have to be addressed in the future.