Synchronize segment register names for i386 and amd64

[Kyle-Kyle]

Description

segment registers have different name for i386, amd64 in archinfo, which is quite annoying
specifically, in archinfo, i386 calls them normally like "cs", "ds", "es", "fs", "gs", "ss", but amd64 calls them "cs_seg", "ds_seg", which is annoying when developing something relevant to those registers.

i386: https://github.com/angr/archinfo/blob/master/archinfo/arch_x86.py#L56
amd64: https://github.com/angr/archinfo/blob/master/archinfo/arch_amd64.py#L442

Alternatives

No response

Additional context

No response

[Kyle-Kyle]

context: I'm developing a segment register filter for angrop: https://github.com/angr/angrop/blob/154310eccc153b44e868b8e454b3043207ea8525/angrop/arch.py#L60