x86/mpeg4qpel: Fix author attribution

Also fix project name

See git blame/log/show and
commit 826f429a
Author: Michael Niedermayer <michaelni@gmx.at>
Date:   Sun Jan 5 15:57:10 2003 +0000

    qpel in mmx2/3dnow
    qpel refinement quality parameter

    Originally committed as revision 1393 to svn://svn.ffmpeg.org/ffmpeg/trunkSigned-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/x86/mpeg4qpel.asm

 ;******************************************************************************
 ;* mpeg4 qpel
+;* Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
 ;* Copyright (c) 2008 Loren Merritt
 ;*
-;* This file is part of Libav.
+;* This file is part of FFmpeg.
 ;*
-;* Libav is free software; you can redistribute it and/or
+;* FFmpeg is free software; you can redistribute it and/or
 ;* modify it under the terms of the GNU Lesser General Public
 ;* License as published by the Free Software Foundation; either
 ;* version 2.1 of the License, or (at your option) any later version.
 ;*
-;* Libav is distributed in the hope that it will be useful,
+;* FFmpeg is distributed in the hope that it will be useful,
 ;* but WITHOUT ANY WARRANTY; without even the implied warranty of
 ;* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 ;* Lesser General Public License for more details.
 ;*
 ;* You should have received a copy of the GNU Lesser General Public
-;* License along with Libav; if not, write to the Free Software
+;* License along with FFmpeg; if not, write to the Free Software
 ;* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 ;******************************************************************************