Implement SIMD latest opcodes and update LLVM to 13.0 (#758)

Implement the latest SIMD opcodes and update LLVM 13.0,
update the llvm build scripts, update the sample workloads‘ build scripts,
and build customized wasi-sdk to build some workloads.
Also refine the CI rules.

Signed-off-by: Wenyong Huang <wenyong.huang@intel.com>

samples/workload/docker/build_workload.sh

@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+#
+# Copyright (C) 2019 Intel Corporation.  All rights reserved.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+
+readonly SCRIPT_PATH=$(dirname "$(realpath "$0")")
+readonly ROOT=$(realpath "${SCRIPT_PATH}"/../../../)
+readonly CURRENT_PATH=$(pwd)
+readonly CURRENT_RELATIVE_ROOT=$(realpath --relative-base ${ROOT} ${CURRENT_PATH})
+readonly VARIANT=$(lsb_release -c | awk '{print $2}')
+
+docker build \
+  --build-arg VARIANT=${VARIANT} \
+  --memory 4G --cpu-quota 50000 \
+  -t wamr_dev_${VARIANT}:0.1 -f "${ROOT}"/ci/Dockerfile "${ROOT}"/ci &&
+  docker run --rm -it \
+    --memory 4G \
+    --cpus ".5" \
+    --name workload_build_env \
+    --mount type=bind,source="${ROOT}",target=/workspace \
+    wamr_dev_${VARIANT}:0.1 \
+    /bin/bash -c "\
+      pwd \
+      && pushd ${CURRENT_RELATIVE_ROOT} \
+      && rm -rf build \
+      && mkdir build \
+      && pushd build \
+      && cmake .. \
+      && cmake --build . --config Release \
+      && popd \
+      && popd \
+      && echo 'Go and find out results under ${CURRENT_RELATIVE_ROOT}/build' "