[Debugify] Expose original debug info preservation check as CC1 option
In order to test the preservation of the original Debug Info metadata
in your projects, a front end option could be very useful, since users
usually report that a concrete entity (e.g. variable x, or function fn2())
is missing debug info. The  is an example of running the utility
on GDB Project.
Differential Revision: https://reviews.llvm.org/D82547