TARGET_OS in config.mak is unused

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@8020 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

configure

@@ -1867,7 +1867,6 @@ fi
 echo "SLIBPREF=$SLIBPREF" >> config.mak
 echo "SLIBSUF=\${BUILDSUF}$SLIBSUF" >> config.mak
 echo "EXESUF=\${BUILDSUF}$EXESUF" >> config.mak
-echo "TARGET_OS=$targetos" >> config.mak
 
 ucarch=`toupper $arch`
 echo "TARGET_ARCH_${ucarch}=yes" >> config.mak