Reapply [NFC] Add fragment-getting functions to DbgRecord (#97705)
Patch [1/x] to fix structured bindings debug info in SROA.
Copy getFragment and getFragmentOrEntireVariable from DbgVariableIntrinsic.
Move FragmentInfo out of DIExpression and DebugInfoMetadata.h into a new file
DbgVariableFragmentInfo.h so it can be included into DebugProgramInstruction.h
without pulling in other includes and classes.