List enabled code in configure output

Originally committed as revision 10921 to svn://svn.ffmpeg.org/ffmpeg/trunk

configure

@@ -1826,6 +1826,18 @@ enabled gpl &&
     echo "License: GPL" ||
     echo "License: LGPL"
 
+for type in decoder encoder parser demuxer muxer protocol bsf; do
+    echo "Enabled ${type}s:"
+    ucname="\$`toupper $type`_LIST"
+    list="`eval echo $ucname`"
+    partlist=""
+    for part in $list; do
+        enabled $part && partlist="$partlist $part"
+    done
+    partlist=`echo $partlist | sed s/_$type//g | tr ' ' '\n' | sort`
+    echo $partlist
+done
+
 echo "Creating config.mak and config.h..."
 
 echo "# Automatically generated by configure - do not modify!" > config.mak