pgsql: Ease out of early destructs.

lib/modules/Sql.pmod/pgsql_util.pmod

@@ -1951,6 +1951,7 @@ class proxy {
 #endif
 
   final void processloop(conxion ci) {
+    mixed err = catch {
       (c = ci)->socket->set_id(procmessage);
       cancelsecret = 0;
       portal = 0;
@@ -1977,6 +1978,8 @@ class proxy {
           cs->sendcmd(SENDOUT);
         }
       }		      // Do not flush at this point, PostgreSQL 9.4 disapproves
+    };
+    if (!err)
       procmessage();
   }