Add missing <application> tags in application doc <refentrytitle>s

Most of them already have this, but some were missing.

Author: Author: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://www.postgresql.org/message-id/flat/87o8pco34z.fsf%40wibble.ilmari.org

doc/src/sgml/ref/initdb.sgml

@@ -9,7 +9,7 @@ PostgreSQL documentation
  </indexterm>
 
  <refmeta>
-  <refentrytitle>initdb</refentrytitle>
+  <refentrytitle><application>initdb</application></refentrytitle>
   <manvolnum>1</manvolnum>
   <refmiscinfo>Application</refmiscinfo>
  </refmeta>

doc/src/sgml/ref/pg_basebackup.sgml

@@ -9,7 +9,7 @@ PostgreSQL documentation
  </indexterm>
 
  <refmeta>
-  <refentrytitle>pg_basebackup</refentrytitle>
+  <refentrytitle><application>pg_basebackup</application></refentrytitle>
   <manvolnum>1</manvolnum>
   <refmiscinfo>Application</refmiscinfo>
  </refmeta>

doc/src/sgml/ref/pg_config-ref.sgml

@@ -9,7 +9,7 @@ PostgreSQL documentation
  </indexterm>
 
  <refmeta>
-  <refentrytitle>pg_config</refentrytitle>
+  <refentrytitle><application>pg_config</application></refentrytitle>
   <manvolnum>1</manvolnum>
   <refmiscinfo>Application</refmiscinfo>
  </refmeta>

doc/src/sgml/ref/pg_dump.sgml

@@ -9,7 +9,7 @@ PostgreSQL documentation
  </indexterm>
 
  <refmeta>
-  <refentrytitle>pg_dump</refentrytitle>
+  <refentrytitle><application>pg_dump</application></refentrytitle>
   <manvolnum>1</manvolnum>
   <refmiscinfo>Application</refmiscinfo>
  </refmeta>

doc/src/sgml/ref/pg_receivewal.sgml

@@ -9,7 +9,7 @@ PostgreSQL documentation
  </indexterm>
 
  <refmeta>
-  <refentrytitle>pg_receivewal</refentrytitle>
+  <refentrytitle><application>pg_receivewal</application></refentrytitle>
   <manvolnum>1</manvolnum>
   <refmiscinfo>Application</refmiscinfo>
  </refmeta>

doc/src/sgml/ref/pg_restore.sgml

@@ -9,7 +9,7 @@ PostgreSQL documentation
  </indexterm>
 
  <refmeta>
-  <refentrytitle>pg_restore</refentrytitle>
+  <refentrytitle><application>pg_restore</application></refentrytitle>
   <manvolnum>1</manvolnum>
   <refmiscinfo>Application</refmiscinfo>
  </refmeta>

doc/src/sgml/ref/pg_verifybackup.sgml

@@ -9,7 +9,7 @@ PostgreSQL documentation
  </indexterm>
 
  <refmeta>
-  <refentrytitle>pg_verifybackup</refentrytitle>
+  <refentrytitle><application>pg_verifybackup</application></refentrytitle>
   <manvolnum>1</manvolnum>
   <refmiscinfo>Application</refmiscinfo>
  </refmeta>