[X86] Disassembly Error, failed to decode `movsxd` instruction again

[venkyqz]

Work environment

Questions	Answers
OS/arch/bits	x86_64 Ubuntu 20.04
Architecture	x86_64
Source of Capstone	git clone, default on next branch.
Version/git commit	v6.0.0, d7be5f9

Instruction bytes giving faulty results

0x63 0x26

Expected results

It should be:

movsxd esp, [rsi]

Steps to get the wrong result

With cstool:

$ ./cstool -d x64 "0x63 0x26"
ERROR: invalid assembly code

Additional Logs, screenshots, source code, configuration dump, ...

Capstone seems to have repeated errors in decoding movsxd instruction in x86. It's confirmed fixed in issues 1093 and 2442. However, the decoding error still exists in Capstone v6.0.0. Other x86 instruction decoders like Zydis, ICED, and XED have no trouble with it.