fix comment

doc/starpu.texi

@@ -1,3 +1,5 @@
+\input texinfo @c -*-texinfo-*-
+
 @c StarPU --- Runtime system for heterogeneous multicore architectures.
 @c
 @c Copyright (C) 2009-2011  Université de Bordeaux 1
@@ -14,8 +16,6 @@
 @c
 @c See the GNU Lesser General Public License in COPYING.LGPL for more details.
 
-\input texinfo @c -*-texinfo-*-
-
 @c %**start of header
 @setfilename starpu.info
 @settitle StarPU Handbook