wrong OSGEO4W_ROOT when installing OSGeo4W to different target directory, see https://trac.osgeo.org/grass/ticket/3724

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@74020 15284696-431f-4ddb-bdfa-cd5b030d7da7

mswindows/osgeo4w/grass.bat.tmpl

@@ -5,13 +5,13 @@ rem # GRASS initialization bat script (OSGeo4W)
 rem #
 rem #########################################################################
 
-SET OSGEO4W_ROOT=@OSGEO4W_ROOT@
-
 rem
 rem Set environmental variables
 rem
-call %OSGEO4W_ROOT%\bin\o4w_env.bat
-call %OSGEO4W_ROOT%\bin\py3_env.bat
+call "%~dp0\o4w_env.bat"
+call py3_env.bat
+@echo off
+
 call %OSGEO4W_ROOT%\apps\grass\grass-@VERSION@\etc\env.bat
 
 rem