patches.html: Add text on the use of the SIgned-off-by: and other tags

Reported-by: Sagar Patel <sagarmp@cs.unc.edu>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
diff --git a/patches.html b/patches.html
index aa4812b..ea543df 100644
--- a/patches.html
+++ b/patches.html
@@ -95,6 +95,34 @@
     [patch] shmop.2: Add "(void *)" cast to RETURN VALUE </pre>
   </li>
   <li>
+    For nontrivial patches, it is helpful if you add a
+    <span class="const">Signed-off-by:</span>
+    tag to certify that you wrote the patch or otherwise have the
+    right to pass it on as an open-source patch.
+    Such a tag is added neas the end of the commit message, and has the form:
+    </br>
+    </br>
+    <span class="const">Signed-off-my: Firstname Lastname &lt;your-email-address&gt;</span>
+    </br>
+    </br>
+    For details, see the section on the "Developer's Certificate of Origin" in the file
+    <a href="https://www.kernel.org/doc/Documentation/process/submitting-patches.rst"><span class="pathname">Documentation/process/submitting-patches.rst</span></a>
+    in the Linux kernel source tree.
+    Where appropriate, other tags documented in that file, such as
+    <span class="const">Reported-by:</span>,
+    <span class="const">Reviewed-by:</span>,
+    <span class="const">Acked-by:</span>,
+    and
+    <span class="const">Suggested-by:</span>
+    can be added to the patch.
+    The
+    <em>man-pages</em> project also uses a
+    <span class="const">Cowritten-by:</span>
+    tag with the obvious meaning.
+      <br>
+      <br>
+  </li>
+  <li>
       <strong>PLEASE NOTE</strong>: for <strong>nontrivial patches</strong>,
       you can save the maintainers a <em>lot</em> of time by attending
       to the following: