Move SOFT_SERIAL_PIN to data driven (#19863)

keyboards/keebio/iris/rev5/config.h

@@ -36,10 +36,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 /* COL2ROW or ROW2COL */
 #define DIODE_DIRECTION COL2ROW
 
-/* serial.c configuration for split keyboard */
-#define SOFT_SERIAL_PIN D0
-
-
 #define BACKLIGHT_PIN B5
 #define BACKLIGHT_LEVELS 5
 #define BACKLIGHT_DEFAULT_LEVEL 3

keyboards/keebio/iris/rev5/info.json

@@ -4,6 +4,9 @@
         "pid": "0x5256",
         "device_version": "5.0.0"
     },
+    "split": {
+        "soft_serial_pin": "D0"
+    },
     "processor": "atmega32u4",
     "bootloader": "qmk-dfu"
 }