[class.inhctor.init] Fix explanation of "error:" in example

The correct explanation is that classes `B1` and `D1` do not have
default constructors, not that they have deleted default constructors.

Fixes NB CA 062 (C++23 CD).

Author: tkoeppe

source/classes.tex

@@ -5875,15 +5875,15 @@
   D1 d(2, 3, 4);    // OK, \tcode{B1} is initialized by calling \tcode{B1(2, 3, 4)},
                     // then \tcode{d.x} is default-initialized (no initialization is performed),
                     // then \tcode{d.y} is initialized by calling \tcode{get()}
-  D1 e;             // error: \tcode{D1} has a deleted default constructor
+  D1 e;             // error: \tcode{D1} has no default constructor
 }
 
 struct D2 : B2 {
   using B2::B2;
   B1 b;
 };
 
-D2 f(1.0);          // error: \tcode{B1} has a deleted default constructor
+D2 f(1.0);          // error: \tcode{B1} has no default constructor
 
 struct W { W(int); };
 struct X : virtual W { using W::W; X() = delete; };