Move encoder config to data driven (#19923)

Co-authored-by: Nick Brassel <nick@tzarc.org>

keyboards/handwired/snatchpad/info.json

@@ -8,6 +8,12 @@
         "pid": "0x7370",
         "device_version": "0.0.1"
     },
+    "encoder": {
+        "rotary": [
+            {"pin_a": "D3", "pin_b": "D2"},
+            {"pin_a": "D0", "pin_b": "D1"}
+        ]
+    },
     "processor": "atmega32u4",
     "bootloader": "atmel-dfu",
     "layouts": {