Replace dynamic macros with constants in memfd test.
Replace dynamic macros with constants in memfd test.

PiperOrigin-RevId: 246433167
Change-Id: Idb9b6c20ee1da193176288dfd2f9d85ec0e69c54

google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor