mb/google/rex: Enable stylus support

This patch enables stylus support by configuring the "GPP_D08" irqs for
rex SoC. This allows the SoC to detect a stylus device, when in use.
However stylus is not a wake up source for the rex.

BUG=b:282256460
Test=Stylus is detected on proto1 device.

Signed-off-by: Dinesh Gehlot <digehlot@google.com>
Change-Id: I84a71aa664698e105b738f8680d0a4751ca1fc72
Reviewed-on: https://review.coreboot.org/c/coreboot/+/71820
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
Reviewed-by: Subrata Banik <subratabanik@google.com>
diff --git a/src/mainboard/google/rex/Kconfig b/src/mainboard/google/rex/Kconfig
index 6aca9e3..9ddd9fd 100644
--- a/src/mainboard/google/rex/Kconfig
+++ b/src/mainboard/google/rex/Kconfig
@@ -33,6 +33,7 @@
 	def_bool n
 	select BOARD_GOOGLE_REX_COMMON
 	select DRIVERS_INTEL_PMC
+	select DRIVERS_GENERIC_GPIO_KEYS
 	select DRIVERS_WWAN_FM350GL
 	select ENABLE_TCSS_DISPLAY_DETECTION if RUN_FSP_GOP
 	select HAVE_SLP_S0_GATE