appveyor: Revert commits adding Cygwin support.

This reverts commits 00ad77b9f6 and
5334dafee2.

This avoids Appveyor build breakage due to Cygwin, but more importantly,
there are several problems with these patches, as highlighted to my
recent mesa-dev mail.  So better to revert for now, and pursue Cygwin
support after these have been address.

scripts/appveyor_cygwin.bat

@@ -1,40 +0,0 @@
-set PKGCACHE=C:\pkgcache
-set CYGWIN_MIRROR=http://cygwin.mirror.constant.com
-
-if _%arch%_ == _x64_ set SETUP=setup-x86_64.exe && set CYGWIN_ROOT=C:\cygwin64
-if _%arch%_ == _x86_ set SETUP=setup-x86.exe && set CYGWIN_ROOT=C:\cygwin
-
-set PATH=%CYGWIN_ROOT%\bin;%SYSTEMROOT%\system32
-
-goto %1
-
-:install
-echo Updating Cygwin and installing build prerequsites
-%CYGWIN_ROOT%\%SETUP% -qnNdO -R "%CYGWIN_ROOT%" -s "%CYGWIN_MIRROR%" -l "%PKGCACHE%" -g -P ^
-bison,^
-ccache,^
-flex,^
-glproto,^
-libX11-devel,^
-libX11-xcb-devel,^
-libXdamage-devel,^
-libXext-devel,^
-libXfixes-devel,^
-libexpat-devel,^
-libllvm-devel,^
-libxcb-dri2-devel,^
-libxcb-glx-devel,^
-libxcb-xfixes-devel,^
-meson,^
-ninja,^
-python3-mako,^
-zlib-devel
-goto :eof
-
-:build_script
-bash -lc "cd $APPVEYOR_BUILD_FOLDER; meson _build -Degl=false --wrap-mode=nofallback && ninja -C _build"
-goto :eof
-
-:after_build
-bash -lc "cd $APPVEYOR_BUILD_FOLDER; ninja -C _build test"
-goto :eof

scripts/appveyor_msvc.bat

@@ -1,38 +0,0 @@
-goto %1
-
-:install
-rem Check git config
-git config core.autocrlf
-rem Check pip
-python --version
-python -m pip --version
-rem Install Mako
-python -m pip install Mako==1.0.7
-rem Install pywin32 extensions, needed by SCons
-python -m pip install pypiwin32
-rem Install python wheels, necessary to install SCons via pip
-python -m pip install wheel
-rem Install SCons
-python -m pip install scons==3.0.1
-call scons --version
-rem Install flex/bison
-set WINFLEXBISON_ARCHIVE=win_flex_bison-%WINFLEXBISON_VERSION%.zip
-if not exist "%WINFLEXBISON_ARCHIVE%" appveyor DownloadFile "https://github.com/lexxmark/winflexbison/releases/download/v%WINFLEXBISON_VERSION%/%WINFLEXBISON_ARCHIVE%"
-7z x -y -owinflexbison\ "%WINFLEXBISON_ARCHIVE%" > nul
-set Path=%CD%\winflexbison;%Path%
-win_flex --version
-win_bison --version
-rem Download and extract LLVM
-if not exist "%LLVM_ARCHIVE%" appveyor DownloadFile "https://people.freedesktop.org/~jrfonseca/llvm/%LLVM_ARCHIVE%"
-7z x -y "%LLVM_ARCHIVE%" > nul
-mkdir llvm\bin
-set LLVM=%CD%\llvm
-goto :eof
-
-:build_script
-call scons -j%NUMBER_OF_PROCESSORS% MSVC_VERSION=14.1 llvm=1
-goto :eof
-
-:after_build
-call scons -j%NUMBER_OF_PROCESSORS% MSVC_VERSION=14.1 llvm=1 check
-goto :eof