Also reverts "[MLIR][Flang][DebugInfo] Convert debug format in MLIR translators"
The patch above introduces behaviour controlled by an LLVM flag into the
Flang driver, which is incorrect behaviour.
This reverts commits:
3cc2710e0dd53bb82742904fa13014018a1137ed.
460408f78b30720950040e336f7b566aa7203269.