[patch, testsuite] Fixes for gdb.python tests on remote Windows host

[Sandra Loosemore]

On 8/12/19 7:34 PM, Christian Biesinger wrote:
> Do the mingw checks in this patch also need to consider cygwin? E.g.:
> This GDB was configured as "x86_64-pc-cygwin".

I believe they are completely separate targets.  I don't know much about 
cygwin, but I assume that Python built for cygwin library is linked with 
the cygwin C library and understands cygwin's fake symbolic links, while 
Python built for the mingw C library certainly does not.  Similarly, 
using ";" instead of ":" in PATH-like things is a Windows thing, while 
I'm pretty sure cygwin emulates the POSIX syntax.

-Sandra