Remove all uses of \sectcode; we can now use logical markup everywhere.
diff --git a/Doc/libregsub.tex b/Doc/libregsub.tex
index 6ee873d..93c955e 100644
--- a/Doc/libregsub.tex
+++ b/Doc/libregsub.tex
@@ -1,4 +1,4 @@
-\section{Standard Module \sectcode{regsub}}
+\section{Standard Module \module{regsub}}
 \label{module-regsub}
 
 \stmodindex{regsub}