MdePkg: Add ARM Serial Port Subtypes to DBG2

The Microsoft Debug Port Table 2 (DBG2) specification revision
October 6, 2015 adds support for Serial Port Subtypes for ARM.

This patch adds these definitions.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Evan Lloyd <evan.lloyd@arm.com>
Reviewed-by: Yao Jiewen <jiewen.yao@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
1 file changed