pyvex fails to decode some Mov instructions with 66 prefix

### Description

pyvex sets jumpkind to 'Ijk_NoDecode' for some MOVSX/MOVZX instructions with '66' prefix.

### Steps to reproduce the bug

Run the following test:

```
import unittest

import pyvex

class Tests(unittest.TestCase):

def test_amd64_movzx_66_prefix(self):
inst_bytes = b"\x66\x0f\xb7\xc0" # movzx ax, ax

irsb = pyvex.IRSB(inst_bytes, 0, pyvex.ARCH_AMD64)
assert irsb.jumpkind == "Ijk_Boring"
assert irsb.size == 4

def test_amd64_movsx_66_prefix(self):
inst_bytes = b"\x66\x0f\xbf\xc0" # movsx ax, ax

irsb = pyvex.IRSB(inst_bytes, 0, pyvex.ARCH_AMD64)
assert irsb.jumpkind == "Ijk_Boring"
assert irsb.size == 4

def test_amd64_movzx_66_prefix_memory(self):
inst_bytes = b"\x66\x45\x0f\xb7\x5c\x27\x6a" # movzx r11w, word ptr [r15 + riz + 0x6a]

irsb = pyvex.IRSB(inst_bytes, 0, pyvex.ARCH_AMD64)
assert irsb.jumpkind == "Ijk_Boring"
assert irsb.size == 7

if __name__ == "__main__":
unittest.main()
```

### Environment

pyvex version 9.2.213.dev0

### Additional context

_No response_