IntelFrameworkModulePkg IsaSerialDxe: Update algorithm to calculate D…

…ivisor

To align the way in MdeModulePkg SerialPortLib and PciSioSerialDxe driver,
Divisor is added by one when the reminder is more than half (16 * BaudRate).

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>

IntelFrameworkModulePkg/Bus/Isa/IsaSerialDxe/Serial.c

@@ -1,7 +1,7 @@
 /** @file
   Serial driver for standard UARTS on an ISA bus.
 
-Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
 This program and the accompanying materials
 are licensed and made available under the terms and conditions of the BSD License
 which accompanies this distribution.  The full text of the license may be found at
@@ -1397,7 +1397,7 @@ IsaSerialSetAttributes (
                        ((UINT32) BaudRate * 16),
                        &Remained
                        );
-  if (Remained != 0) {
+  if (Remained >= ((UINT32) BaudRate * 8)) {
     Divisor += 1;
   }