std.Target: remove Abi.code16

This functionality -- if it's actually needed -- can be reintroduced through
some other mechanism. An ABI is clearly not the right way to represent it.

closes #25918
16fc083f2bAlex Rønne Petersen committed on 11/23/2025, 9:22:03 AMparent6d543bc
5 files changedLine totals unavailable