freertos: Copy IDF xtensa port files

This commit copies over ESP-IDF Xtensa portable files to the
FreeRTOS-Kernel-SMP directory. No changes were made, this commit
only copies the portable source files.

Notes:
- This commit WILL NOT compile
- Some SPDX header dates were updated to pass pre-commit check

components/freertos/FreeRTOS-Kernel-SMP/portable/xtensa/xtensa_init.c

@@ -0,0 +1,62 @@
+/*
+ * SPDX-FileCopyrightText: 2015-2019 Cadence Design Systems, Inc.
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ * SPDX-FileContributor: 2016-2022 Espressif Systems (Shanghai) CO LTD
+ */
+/*
+ * Copyright (c) 2015-2019 Cadence Design Systems, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/*
+ * XTENSA INITIALIZATION ROUTINES CODED IN C
+ *
+ * This file contains miscellaneous Xtensa RTOS-generic initialization functions
+ * that are implemented in C.
+ */
+
+
+#ifdef XT_BOARD
+#include "xtensa/xtbsp.h"
+#endif
+
+#include "xtensa_rtos.h"
+#include "sdkconfig.h"
+#include "esp_private/esp_clk.h"
+
+#ifdef XT_RTOS_TIMER_INT
+
+unsigned _xt_tick_divisor = 0;  /* cached number of cycles per tick */
+
+void _xt_tick_divisor_init(void)
+{
+    _xt_tick_divisor = esp_clk_cpu_freq() / XT_TICK_PER_SEC;
+}
+
+/* Deprecated, to be removed */
+int xt_clock_freq(void)
+{
+    return esp_clk_cpu_freq();
+}
+
+#endif /* XT_RTOS_TIMER_INT */