Doc: remove misleading claim in documentation of PQreset().

This text claimed that the reconnection would occur "to the same
server", but there is no such guarantee in the code, nor would
insisting on that be an improvement.

Back-patch to v10 where multi-host connection strings were added.

Discussion: https://postgr.es/m/1095901.1611268376@sss.pgh.pa.us

doc/src/sgml/libpq.sgml

@@ -645,8 +645,8 @@ void PQreset(PGconn *conn);
 
       <para>
        This function will close the connection
-       to the server and attempt to  reestablish  a  new
-       connection to the same server, using all the same
+       to the server and attempt to establish a new
+       connection, using all the same
        parameters previously used.  This might be useful for
        error recovery if a working connection is lost.
       </para>
@@ -669,7 +669,7 @@ PostgresPollingStatusType PQresetPoll(PGconn *conn);
 
       <para>
        These functions will close the connection to the server and attempt to
-       reestablish a new connection to the same server, using all the same
+       establish a new connection, using all the same
        parameters previously used. This can be useful for error recovery if a
        working connection is lost. They differ from <xref linkend="libpq-PQreset"/> (above) in that they
        act in a nonblocking manner. These functions suffer from the same