LICENSE: Clarify --enable-nonfree.

Using the configure option --enable-nonfree makes the resulting binary unredistributable.

LICENSE.md

@@ -103,10 +103,7 @@ license version needs to be upgraded by passing `--enable-version3` to configure
 There are certain libraries you can combine with FFmpeg whose licenses are not
 compatible with the GPL and/or the LGPL. If you wish to enable these
 libraries, even in circumstances that their license may be incompatible, pass
-`--enable-nonfree` to configure. But note that if you enable any of these
-libraries the resulting binary will be under a complex license mix that is
-more restrictive than the LGPL and that may result in additional obligations.
-It is possible that these restrictions cause the resulting binary to be
+`--enable-nonfree` to configure. This will cause the resulting binary to be
 unredistributable.
 
 The Fraunhofer FDK AAC and OpenSSL libraries are under licenses which are