[PATCH] testsuite: use cygpath to convert from Unix to Windows paths

[Eli Zaretskii]

> Cc: gdb-patches <gdb-patches@sourceware.org>, Eli Zaretskii <eliz@gnu.org>
> From: Simon Marchi <simon.marchi@efficios.com>
> Date: Wed, 11 Mar 2020 15:09:10 -0400
> 
> However, the solution I proposed won't work with the non-MinGW-w64 MinGW, as
> it does not ship with cygpath.  Here is another version of the patch that uses
> `pwd -W` to get the same information.

Right, using "pwd -W" was exactly what I wanted to propose for this
purpose.