espsystem: Rearchitecture and fix eh_frame_parser bugs

eh_frame_parser is architecture independent, thus the files have
been rearchitectured. Some bugs have been fixed in the test.
A README file has also been added to eh_frame_parser host test
directory.

eh_frame_parser is now able to detect empty gaps in .eh_frame_hdr
table (missing DWARF information).
Fix a bug occuring when parsing backtraces originated from abort().
Fix build missing dependencies issue.

components/esp_system/include/eh_frame_parser.h

@@ -0,0 +1,35 @@
+// Copyright 2020 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.
+
+#ifndef EH_FRAME_PARSER_H
+#define EH_FRAME_PARSER_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief Print backtrace for the given execution frame.
+ *
+ * @param frame_or Snapshot of the CPU registers when the program stopped its
+ *                 normal execution. This frame is usually generated on the
+ *                 stack when an exception or an interrupt occurs.
+ */
+void esp_eh_frame_print_backtrace(const void *frame_or);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif