[Keyboard] Zen keyboard update for Rev2 (#5522)

* Updated Zen keyboard for rev2 support

* Fixing r1 compile errors

* PR feedback and changes for Proton-C compile errors

keyboards/zen/rev2/keymaps/debug/keymap.c

@@ -0,0 +1,19 @@
+#include QMK_KEYBOARD_H
+#include <stdio.h>
+
+// extern keymap_config_t keymap_config;
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = { { { KC_TRNS } } };
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+    static char buf[10] = " ";
+
+    if (record->event.pressed) {
+      snprintf(buf, 10, "C%dR%d ", record->event.key.col, record->event.key.row);
+
+      send_string(buf);
+    }
+    return false;
+
+  return true;
+}