Fix mingw version back to working version with Golang
Appveyor choco install updated to a newer version of mingw which at the
moment is breaking Golang 1.11 compiles.
@@ -15,7 +15,7 @@ environment:
- GO_VERSION: 1.11
before_build:
- - choco install -y mingw
+ - choco install -y mingw --version 5.3.0
# Install Go
- rd C:\Go /s /q
- appveyor DownloadFile https://storage.googleapis.com/golang/go%GO_VERSION%.windows-amd64.zip
