run script from build dir, not source dir

git-svn-id: svn://bind10.isc.org/svn/bind10/trunk@2347 e5f2f494-b856-4b98-b285-d166d9295462

src/bin/loadzone/run_loadzone.sh.in

@@ -21,5 +21,5 @@ export PYTHON_EXEC
 PYTHONPATH=@abs_top_builddir@/src/lib/python
 export PYTHONPATH
 
-LOADZONE_PATH=@abs_top_srcdir@/src/bin/loadzone
+LOADZONE_PATH=@abs_top_builddir@/src/bin/loadzone
 exec ${LOADZONE_PATH}/b10-loadzone $*