QLatin1StringView: add missing (const_)pointer nested typedef

It's required for C++ containers.

Change-Id: Id5b51e1af22ac6e452019e976f50c727bbba6948
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
Reviewed-by: Ahmad Samir <a.samirh78@gmail.com>

src/corelib/text/qlatin1stringview.h

@@ -182,6 +182,8 @@ public:
     }
 
     using value_type = const char;
+    using pointer = value_type*;
+    using const_pointer = pointer;
     using reference = value_type&;
     using const_reference = reference;
     using iterator = value_type*;

src/corelib/text/qlatin1stringview.qdoc

@@ -102,6 +102,14 @@
     on 64-bit architectures.
 */
 
+/*!
+    \typedef QLatin1StringView::pointer
+    \typedef QLatin1StringView::const_pointer
+    \since 6.7
+
+    Alias for \c{value_type *}. Provided for compatibility with the STL.
+*/
+
 /*!
     \typedef QLatin1StringView::reference
     \since 5.10