git-hooks: remove hint in './g -z'

In the patch 05ea4ac195 the hint
is too mutch and the elsewhere I think it makes no sense, remove.

Change-Id: I1c13e593f673f2cab9a307f57f59efa1fbd903c9
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/149761
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>

g

@@ -147,10 +147,6 @@ refresh_all_hooks()
         fi
     fi
 
-    if [ $wingit -eq 0 ] && [ "$OSTYPE" == "cygwin" ] ; then
-        echo "When you using GIT for Windows, and get git-error look to .git-hooks/README"
-    fi
-
     popd > /dev/null
 
 }