doxygen: add newline after \file

While \file doesn't need an argument, it can't have another doxy
command after it.

source/blender/python/intern/bpy_interface_atexit.c

@@ -14,7 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-/** \file \ingroup pythonintern
+/** \file
+ * \ingroup pythonintern
  *
  * This file inserts an exit callback into pythons 'atexit' module.
  * Without this sys.exit() can crash because blender is not properly closing