Disassembly should print "data16" prefix in Intel style

Maybe the recommended style changes and that's why we don't print "data16" in Intel style, yet xed now prints it?

From #8043:
```
$ for i in cf 9c 9d 60 61; do ~/dr/releases/DynamoRIO-Linux-11.91.20664/bin32/drdisas -syntax intel 66 $i; echo "foo 0x66 0x${i}" | ~/extsw/xed/obj/wkit/bin/xed -32 -F foo; done
66 cf iretw
data16 iret
66 9c pushfw
data16 pushf
66 9d popfw
data16 popf
66 60 pushaw
data16 pusha
66 61 popaw
data16 popa
```

Reproduce the examples with drdisas using -syntax intel and compare their output with the shown xed results for bytes 66 cf, 9c, 9d, 60, and 61. Trace the Intel-style disassembly entry point from that command, then verify that each affected instruction reports the data16 prefix and that existing disassembly behavior remains covered by tests.

Written by the indexing model from the issue text.