docs: make Robbert happy, don't use 2 as mnemonic for "to"

docs/iris.sty

@@ -323,8 +323,8 @@
 \newcommand{\step}{\ra}
 \newcommand{\lctx}{K}
 
-\newcommand{\toval}{\mathrm{expr2val}}
-\newcommand{\ofval}{\mathrm{val2expr}}
+\newcommand{\toval}{\mathrm{expr\any to\any val}}
+\newcommand{\ofval}{\mathrm{val\any to\any expr}}
 \newcommand{\atomic}{\mathrm{atomic}}
 \newcommand{\red}{\mathrm{red}}
 \newcommand{\Lang}{\Lambda}