[linalg.reqs.val] Fix use of \defnadjx for value types (cplusplus#7374)

source/numerics.tex

@@ -11722,7 +11722,7 @@
 \pnum
 Throughout \ref{linalg},
 the following types are
-\defnadjx{linear algebra}{value type}{linear algebra value types}:
+\defnadjx{linear algebra}{value types}{value type}:
 \begin{itemize}
 \item
 the \tcode{value_type} type alias of