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>