[dfsan] Instrument origin variable and function definitions

This is a part of https://reviews.llvm.org/D95835.

Reviewed-by: morehouse, gbalats

Differential Revision: https://reviews.llvm.org/D96977

GitOrigin-RevId: 7e658b2fdcccb5bbedef3f90c4d5ea5ca7de9268
2 files changed