[dcl.init] Replace \tcode with more semantically appropriate \terminal

Author: zygoloid

source/declarators.tex

@@ -2469,7 +2469,7 @@
 
 \begin{bnf}
 \nontermdef{designator}\br
-    \tcode{.} identifier
+    \terminal{.} identifier
 \end{bnf}
 
 \begin{bnf}