mb/google/rex: add macro for touchscreen IRQ

BUG=b:278783755

Signed-off-by: Eran Mitrani <mitrani@google.com>
Change-Id: I2a6de778c7ab30a9946e100cb70c092ba98496e3
Reviewed-on: https://review.coreboot.org/c/coreboot/+/74944
Reviewed-by: Subrata Banik <subratabanik@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/rex/variants/baseboard/rex/include/baseboard/gpio.h

@@ -22,5 +22,7 @@
 #define GPIO_MEM_CONFIG_2	GPP_E01
 #define GPIO_MEM_CONFIG_3	GPP_E12
 #define GPIO_MEM_CH_SEL		GPP_E13
+/* Touchscreen IRQ */
+#define TOUCH_SCR_IRQ		GPP_C07_IRQ
 
 #endif /* __BASEBOARD_GPIO_H__ */