[dfsan] Propagate origins for callsites

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

Each customized function has two wrappers. The
first one dfsw is for the normal shadow propagation. The second one dfso is used
when origin tracking is on. It calls the first one, and does additional
origin propagation. Which one to use can be decided at instrumentation
time. This is to ensure minimal additional overhead when origin tracking
is off.

Reviewed-by: morehouse

Differential Revision: https://reviews.llvm.org/D97483