Add a comment noting that the dependency information is stored in
Makefile.deps.
diff --git a/Doc/Makefile b/Doc/Makefile
index c2ceb7c..2da6fab 100644
--- a/Doc/Makefile
+++ b/Doc/Makefile
@@ -48,6 +48,9 @@
# the html/ directory. If you want to fix the GNU info process, look
# in the info/ directory; please send patches to python-docs@python.org.
+# This Makefile only includes information on how to perform builds; for
+# dependency information, see Makefile.deps.
+
# Customizations -- you *may* have to edit these
# you could set this to a4