Build: Don't install TODO.

(cherry picked from commit f3440e78c9517db75bfa52e1a378fad60b073bbe)

Makefile.am

@@ -25,7 +25,6 @@ dist_doc_DATA = \
 	NEWS \
 	README \
 	THANKS \
-	TODO \
 	doc/faq.txt \
 	doc/history.txt \
 	doc/xz-file-format.txt \
@@ -74,6 +73,7 @@ EXTRA_DIST = \
 	COPYING.LGPLv2.1 \
 	INSTALL.generic \
 	PACKAGERS \
+	TODO \
 	build-aux/manconv.sh \
 	build-aux/version.sh