fixed 13036a0b from https://gitee.com/liyufan123/third_party_musl/pulls/850

Fix codecheck for build waring

Issue:#I6NCRY
Test: Build & Boot devices
Signed-off-by: Nliyufan <liyufan5@huawei.com>

porting/linux/user/src/hook/musl_socket_preinit.c

@@ -38,7 +38,7 @@ static void clear_socket_function()
 static void socket_finalize()
 {
 	((finalize_func_type)shared_lib_func[FINALIZE_FUNC])();
-	__current_dispatch = NULL;
+	__current_dispatch = 0;
 	__socket_hook_begin_flag = false;
 	// Don't dlclose because hidumper crash
 }
@@ -51,7 +51,7 @@ static bool finish_install_ohos_socket_hooks(const char* options)
 		return false;
 	}
 
-	int ret_value = atexit(socket_finalize);
+	atexit(socket_finalize);
 	return true;
 }
 
@@ -106,7 +106,7 @@ static void install_ohos_socket_hook()
 		return;
 	}
 
-	__current_dispatch = NULL;
+	__current_dispatch = 0;
 	shared_library_handle = load_socket_hook_shared_library();
 	if (shared_library_handle == NULL) {
 		return;
@@ -116,7 +116,7 @@ static void install_ohos_socket_hook()
 		__ohos_socket_hook_shared_library = (long long)shared_library_handle;
 		__current_dispatch = (long long)(&__musl_libc_socket_dispatch);
 	} else {
-		__ohos_socket_hook_shared_library = NULL;
+		__ohos_socket_hook_shared_library = 0;
 		dlclose((void *)shared_library_handle);
 	}
 }