Update cent/ucent deprecated docs

[ntrel]

Also list std.int128. ~~Add TROW_DEPRECATED1 macro (the <del> tag of GDEPRECATED doesn't work outside of <td>).~~ Mark cent/ucent as deprecated in basic types & add note under table.

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	24710	normal	cent and ucent not marked as deprecated in basic types spec