### Summary
We have internally seen cases like this
`DW_OP_lit0, DW_OP_stack_value, DW_OP_piece 0x28`
where we have longer op pieces than what Scalar supports (32, 64 or 128
bits). In these cases LLDB is currently hitting the assertion
`assert(ap_int.getBitWidth() >= bit_size);`
We are extending the generated APInt to the piece size by filling zeros.
### Test plan
Added a unit to cover this case.
### Reviewers
@clayborg , @jeffreytan81 , @Jlalond
a0db29d647