[GPIO][PCBA]Add PCBA stage to system properties

PCB Variant Table:
 GPIO_99	GPIO_98		GPIO_97
 0		 0		 0		EP0
 0		 0		 1		EP1
 0		 1		 0		EP2
 0		 1		 1		FP
 1               0               0              MP

RiskArea: GPIO

Change-Id: Id6ca2ce6573e42d09ddf3eae82f4e39fdbf25233
1 file changed