add test for chdir and getcwd

tests/wasix/chdir-getcwd/main.c

@@ -0,0 +1,30 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+int main()
+{
+    char cwd[1024];
+
+    int status = EXIT_FAILURE;
+
+    if (chdir("/tmp") != 0)
+    {
+        goto end;
+    }
+
+    if (getcwd(cwd, sizeof(cwd)) == NULL)
+    {
+        goto end;
+    }
+
+    if (strcmp(cwd, "/tmp") == 0)
+    {
+        status = EXIT_SUCCESS;
+    }
+
+end:
+    printf("%d", status);
+    exit(status);
+}

tests/wasix/chdir-getcwd/run.sh

@@ -0,0 +1,3 @@
+$WASMER -q run main.wasm > output
+
+printf "0" | diff -u output - 1>/dev/null