Remove redundant variable setting.

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@7372 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

configure

@@ -1078,7 +1078,6 @@ EOF
     fi
     video4linux="no"
     video4linux2="no"
-    bktr="no"
     audio_oss="no"
     dv1394="no"
     dc1394="no"