[DebugInfo] Upgrade `dbg.addr` to `dbg.value`

As part of removing `dbg.addr`, this upgrades any calls to `dbg.value` with
`DW_OP_deref` prepended onto the value expression.

Part of `dbg.addr` removal
Discussed in https://discourse.llvm.org/t/what-is-the-status-of-dbg-addr/62898

Differential Revision: https://reviews.llvm.org/D144793