profiles/prefix/winnt/x86: kill versioned profiles, for generic one

profiles/prefix/winnt/x86: kill versioned profiles, for generic one

Having the windows version in profile does not make so much sense,
instead the MSVC version would.  But as the profile is identical for any
MSVC version except for CHOST, the profile does not set CHOST but relies
on the user to choose CHOST as argument to prefix-stack-setup, one out
of the list from (sys-devel/parity) 'parity-setup --list-available'.
The generic profile was added earlier, without the profiles.desc entry.

Signed-off-by: Michael Haubenwallner <haubi@gentoo.org>