std.math.big.int: Initialize limbs in addWrap

When a big.Int.Mutable had more than two limbs, it was possible for
this function to change the `len` field without zeroing limbs in the
active range. These uninitialized limbs would then be used in
`truncate()` and could cause invalid results.

Closes #13571
e8fdb249b6Stevie Hryciw committed on 4/20/2023, 11:00:37 PM· committed by Andrew Kelleyparent7d90410
2 files changedLine totals unavailable