soc/amd/cezanne/acpi: Change GPIO controller interrupt to shared

The Majolica UEFI ACPI tables have this listed as shared. It's already a
level interrupt, so no reason it shouldn't be shared.

This change makes it so Windows can correctly initialize the GPIO
controller.

BUG=b:186212501
TEST=Boot guybrush to windows and see GPIO controller functional. Also
boot guybrush to windows and verify GPIO controller still works.

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: I48c6d548a2a8d67599f25e37eeafc90764d9e2d2
Reviewed-on: https://review.coreboot.org/c/coreboot/+/56177
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>

src/soc/amd/cezanne/acpi/mmio.asl

@@ -34,7 +34,7 @@ Device (GPIO)
 				ResourceConsumer,
 				Level,
 				ActiveLow,
-				Exclusive, , , IRQR)
+				Shared, , , IRQR)
 			{ 0 }
 			Memory32Fixed (ReadWrite, ACPIMMIO_GPIO0_BASE, 0x400)
 		}