Fix spec test workflow issue and CI Dockerfile issue (#810)

Fix llvm binaries cache missed issue in spec test workflow,
fix CI Dockerfile issue and refine code format for libc_builtin_wrapper.c.

.github/workflows/spec_test.yml

@@ -34,7 +34,7 @@ concurrency:
 
 env:
   DEFAULT_TEST_OPTIONS: "-s spec"
-  LLVM_CACHE_SUFFIX: "build-llvm_libraries"
+  LLVM_CACHE_SUFFIX: "build-llvm_libraries_ex"
   MULTI_MODULES_TEST_OPTIONS: "-s spec -M"
   SIMD_TEST_OPTIONS: "-s spec -S"
   THREADS_TEST_OPTIONS: "-s spec -p"

ci/Dockerfile

@@ -1,7 +1,7 @@
 # Copyright (C) 2019 Intel Corporation.  All rights reserved.
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
-ARG VARIANT=need_to_assign
+ARG VARIANT=focal
 FROM ubuntu:${VARIANT}
 
 ARG DEBIAN_FRONTEND=noninteractive
@@ -13,7 +13,7 @@ RUN apt update \
       libgcc-9-dev lib32gcc-9-dev lsb-release \
       ninja-build  ocaml ocamlbuild python2.7 \
       software-properties-common tree tzdata \
-      unzip url valgrind vim wget zip
+      unzip valgrind vim wget zip
 
 #
 # CMAKE (https://apt.kitware.com/)

core/iwasm/libraries/libc-builtin/libc_builtin_wrapper.c

@@ -1128,10 +1128,10 @@ print_f64_wrapper(wasm_exec_env_t exec_env, double f64)
 }
 #endif /* WASM_ENABLE_SPEC_TEST */
 
-#define REG_NATIVE_FUNC(func_name, signature)            \
-    {                                                    \
-#func_name, func_name##_wrapper, signature, NULL \
-    }
+/* clang-format off */
+#define REG_NATIVE_FUNC(func_name, signature) \
+    { #func_name, func_name##_wrapper, signature, NULL }
+/* clang-format on */
 
 static NativeSymbol native_symbols_libc_builtin[] = {
     REG_NATIVE_FUNC(printf, "($*)i"),