Update IDF to a0468b2 (#2108)

* Update IDF to a0468b2

* add missing ld file

* Fix PIO builds and change coex policy

tools/sdk/include/bootloader_support/bootloader_util.h

@@ -0,0 +1,34 @@
+// Copyright 2018 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+
+#include <stddef.h>
+
+/**
+ * @brief Check if half-open intervals overlap
+ *
+ * @param start1  interval 1 start
+ * @param end1    interval 1 end
+ * @param start2  interval 2 start
+ * @param end2    interval 2 end
+ * @return true iff [start1; end1) overlaps [start2; end2)
+ */
+static inline bool bootloader_util_regions_overlap(
+        const intptr_t start1, const intptr_t end1,
+        const intptr_t start2, const intptr_t end2)
+{
+    return (end1 > start2 && end2 > start1) ||
+           !(end1 <= start2 || end2 <= start1);
+}