[Keyboard] Add mini_ten_key_plus (#15568)

Co-authored-by: Drashna Jaelre <drashna@live.com>
Co-authored-by: Ryan <fauxpark@gmail.com>

keyboards/mini_ten_key_plus/mini_ten_key_plus.c

@@ -0,0 +1,15 @@
+// Copyright 2021 minibois (@minibois)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "mini_ten_key_plus.h"
+
+/* Rotary Encoder's function (currently volume up/down) */
+bool encoder_update_kb(uint8_t index, bool clockwise) {
+    if (!encoder_update_user(index, clockwise)) { return false; }
+        if (clockwise) {
+            tap_code16(KC_RIGHT_PAREN);
+        } else {
+            tap_code16(KC_LEFT_PAREN);
+        }
+    return true;
+}