xfail charptr test that uses unaligned memcpy which isn't supported on managed

Author: timfel

graalpython/lib-graalpython/modules/hpy/test/debug/test_charptr.py

@@ -150,6 +150,7 @@ def test_charptr_write_ptr(compiler, python_subprocess):
     assert result.stderr == b""
 
 
+@pytest.mark.xfail(__graalpython__.platform_id == "managed", reason="unaligned memcpy is not supported")
 def test_charptr_correct_usage(compiler):
     mod = compiler.make_module("""
         #include <string.h>