[dcl.init.ref] Add missing comma, turn into sub-bullets

Author: Tsche

source/declarations.tex

@@ -6268,7 +6268,11 @@
 
 \item Otherwise, if the initializer expression
 \begin{itemize}
-\item is an rvalue (but not a bit-field) or an lvalue of function type and
+\item is either
+\begin{itemize}
+\item an rvalue (but not a bit-field), or 
+\item an lvalue of function type, and
+\end{itemize}
 ``\cvqual{cv1} \tcode{T1}'' is
 reference-compatible with ``\cvqual{cv2} \tcode{T2}'', or