kill error messages from failed svn revision extraction commands

Originally committed as revision 9363 to svn://svn.ffmpeg.org/ffmpeg/trunk

version.sh

 #!/bin/sh
 
 svn_revision=`cd "$1" && LC_ALL=C svn info 2> /dev/null | grep Revision | cut -d' ' -f2`
-test $svn_revision || svn_revision=`cd "$1" && grep revision .svn/entries | \
-                                    cut -d '"' -f2 2> /dev/null`
-test $svn_revision || svn_revision=`cd "$1" && sed -n '/^dir$/{n;p;q}' < .svn/entries`
+test $svn_revision || svn_revision=`cd "$1" && grep revision .svn/entries 2>/dev/null | cut -d '"' -f2`
+test $svn_revision || svn_revision=`cd "$1" && sed -n -e '/^dir$/{n;p;q}' .svn/entries 2>/dev/null`
 test $svn_revision || svn_revision=UNKNOWN
 
 NEW_REVISION="#define FFMPEG_VERSION \"SVN-r$svn_revision\""