(alx-0014r6-A) Refactor syntax of include directives

Signed-off-by: Alejandro Colomar <[email protected]>

Author: alejandro-colomar

source/preprocessor.tex

@@ -47,7 +47,7 @@
 
 \begin{bnf}
 \nontermdef{control-line}\br
-    \terminal{\# include} pp-tokens new-line\br
+    include-directive\br
     pp-import\br
     \terminal{\# embed \ } pp-tokens new-line\br
     \terminal{\# define } identifier replacement-list new-line\br
@@ -696,6 +696,11 @@
 \indextext{inclusion!source file|see{preprocessing directive, source-file inclusion}}%
 \indextext{\idxcode{\#include}}%
 
+\begin{bnf}
+\nontermdef{include-directive}\br
+    \terminal{\# include} pp-tokens new-line\br
+\end{bnf}
+
 \pnum
 A \defnadj{header}{search} for a sequence of characters
 searches a sequence of places for a header