[clang] [llvm] [clang][ScanDeps] Allow PCHs to have different VFS overlays (PR #82294)

[Jan Svoboda via cfe-commits]

https://github.com/jansvoboda11 commented:

Just to clarify, this patch doesn't attempt to solve the case where the Clang can crash when the VFS overlay files are different between the PCH and the TU, since that's existing behavior. Correct?

https://github.com/llvm/llvm-project/pull/82294