doc: Fix up spacing around verbatim DocBook elements

doc/src/sgml/libpq.sgml

@@ -5437,18 +5437,18 @@ int PQpipelineSync(PGconn *conn);
     round-trip to get the results it needs. However, it's often possible to
     adjust the client design to exchange the required information server-side.
     Read-modify-write cycles are especially good candidates; for example:
-    <programlisting>
+<programlisting>
 BEGIN;
 SELECT x FROM mytable WHERE id = 42 FOR UPDATE;
 -- result: x=2
 -- client adds 1 to x:
 UPDATE mytable SET x = 3 WHERE id = 42;
 COMMIT;
-    </programlisting>
+</programlisting>
     could be much more efficiently done with:
-    <programlisting>
+<programlisting>
 UPDATE mytable SET x = x + 1 WHERE id = 42;
-    </programlisting>
+</programlisting>
    </para>
 
    <para>

doc/src/sgml/logicaldecoding.sgml

@@ -830,10 +830,10 @@ typedef bool (*LogicalDecodeFilterPrepareCB) (struct LogicalDecodingContext *ctx
       check if the plugin has already received this <command>PREPARE</command>
       in which case it can either error out or skip the remaining changes of 
       the transaction.
-      <programlisting>
-       typedef void (*LogicalDecodeBeginPrepareCB) (struct LogicalDecodingContext *ctx,
+<programlisting>
+typedef void (*LogicalDecodeBeginPrepareCB) (struct LogicalDecodingContext *ctx,
                                              ReorderBufferTXN *txn);
-      </programlisting>
+</programlisting>
      </para>
     </sect3>
 
@@ -847,11 +847,11 @@ typedef bool (*LogicalDecodeFilterPrepareCB) (struct LogicalDecodingContext *ctx
       rows will have been called before this, if there have been any modified
       rows. The <parameter>gid</parameter> field, which is part of the
       <parameter>txn</parameter> parameter, can be used in this callback.
-      <programlisting>
-       typedef void (*LogicalDecodePrepareCB) (struct LogicalDecodingContext *ctx,
+<programlisting>
+typedef void (*LogicalDecodePrepareCB) (struct LogicalDecodingContext *ctx,
                                         ReorderBufferTXN *txn,
                                         XLogRecPtr prepare_lsn);
-      </programlisting>
+</programlisting>
      </para>
     </sect3>
 
@@ -863,11 +863,11 @@ typedef bool (*LogicalDecodeFilterPrepareCB) (struct LogicalDecodingContext *ctx
       whenever a transaction <command>COMMIT PREPARED</command> has been decoded.
       The <parameter>gid</parameter> field, which is part of the
       <parameter>txn</parameter> parameter, can be used in this callback.
-      <programlisting>
-       typedef void (*LogicalDecodeCommitPreparedCB) (struct LogicalDecodingContext *ctx,
+<programlisting>
+typedef void (*LogicalDecodeCommitPreparedCB) (struct LogicalDecodingContext *ctx,
                                                ReorderBufferTXN *txn,
                                                XLogRecPtr commit_lsn);
-      </programlisting>
+</programlisting>
      </para>
     </sect3>
 
@@ -885,12 +885,12 @@ typedef bool (*LogicalDecodeFilterPrepareCB) (struct LogicalDecodingContext *ctx
       it can apply the rollback, otherwise, it can skip the rollback operation. The
       <parameter>gid</parameter> alone is not sufficient because the downstream
       node can have a prepared transaction with same identifier.
-      <programlisting>
-       typedef void (*LogicalDecodeRollbackPreparedCB) (struct LogicalDecodingContext *ctx,
+<programlisting>
+typedef void (*LogicalDecodeRollbackPreparedCB) (struct LogicalDecodingContext *ctx,
                                                  ReorderBufferTXN *txn,
                                                  XLogRecPtr prepare_end_lsn,
                                                  TimestampTz prepare_time);
-      </programlisting>
+</programlisting>
      </para>
     </sect3>