[BOLT] Add BB index to BAT

Add input basic block index to BAT metadata. This addresses the case
where some basic blocks are eliminated, and output index is not equal
to the input block index. These indices are used in non-stale-matching
mode.

Increases BAT section size to:
- large binary: 39521512 bytes (1.02x original),
- medium binary: 3799988 bytes (0.64x),
- small binary: 920 bytes (0.64x).

Test Plan:
Updated bolt-address-translation{,-yaml}.test

Pull Request: https://github.com/llvm/llvm-project/pull/86044