Import mbedtls-3.6.2

Imports Mbed TLS 3.6.2 from https://github.com/Mbed-TLS/mbedtls.git
tags mbedtls-3.6.2, v3.6.2

Files that are not needed are removed:

cd lib/libmbedtls
rm -rf mbedtls
cp -R path/to/mbedtls-3.6.2/mbedtls .
cd mbedtls
rm CMakeLists.txt DartConfiguration.tcl Makefile
rm .gitignore .travis.yml .pylintrc .globalrc .mypy.ini BRANCHES.md
rm include/.gitignore include/CMakeLists.txt library/.gitignore
rm library/CMakeLists.txt library/Makefile
rm -r cmake
rm -rf .git .github doxygen configs programs scripts tests visualc
rm -rf 3rdparty ChangeLog.d docs pkgconfig .gitmodules .readthedocs.yaml
rm library/mps_*
cd ..
git add mbedtls

This is a complete overwrite of previous code so earlier changes in the
previous branch import/mbedtls-3.6.0 will be added on top of this
commit.

Signed-off-by: Sungbae Yoo <sungbaey@nvidia.com>
diff --git a/lib/libmbedtls/mbedtls/library/entropy_poll.c b/lib/libmbedtls/mbedtls/library/entropy_poll.c
index 794ee03..611768c 100644
--- a/lib/libmbedtls/mbedtls/library/entropy_poll.c
+++ b/lib/libmbedtls/mbedtls/library/entropy_poll.c
@@ -5,10 +5,12 @@
  *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
  */
 
-#if defined(__linux__) || defined(__midipix__) && !defined(_GNU_SOURCE)
+#if defined(__linux__) || defined(__midipix__)
 /* Ensure that syscall() is available even when compiling with -std=c99 */
+#if !defined(_GNU_SOURCE)
 #define _GNU_SOURCE
 #endif
+#endif
 
 #include "common.h"