As ACRN prepares to support platforms with multiple IO-APICs,
GSI is a better way to represent physical and virtual INTx interrupt
source.
1) This patch replaces usage of "pin" with "gsi" whereever applicable
across the modules.
2) PIC pin to gsi is trickier and needs to consider the usage of
"Interrupt Source Override" structure in ACPI for the corresponding VM.
Tracked-On: #4151
Signed-off-by: Sainath Grandhi <sainath.grandhi@intel.com>
Acked-by: Eddie Dong <eddie.dong@Intel.com>
ec86921444