cygwin ld import library issue fix (removing unused "_nm_" symbols)

[Ralf Habacker]

Hi Danny,

> Yes, this looks very nice, but does it works against current CVS?

This patch is a minor change, which could be reviewed easy, but I have got
trouble using the current cvs head (binutils 2-12.xx) release from
sources.redhat.com.
It produces undefined symbols compiling dll/apps and that means cygwin support
seems to be broken. Because I hadn't enough time to check this, I installed the
sources from the last official cygwin binutils release (GNU ld version 2.11.92
20011001) and have applied this patch.

Ralf