Fix if block

appveyor.yml

@@ -56,8 +56,7 @@ after_build:
   - if "%APPVEYOR_BUILD_WORKER_IMAGE%"=="Visual Studio 2017" (
         if "%platform%"=="x64" (
             iscc packaging\windows-innosetup\script_x64.iss
-        )
-        if "%platform%"!="x64" (
+        ) else (
             iscc packaging\windows-innosetup\script_x86.iss
         )
     )