[clang] [flang] [Flang][Driver][Offload] Support -Xoffload-linker argument in Flang (PR #109907)

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agozillon wrote:

Added the new suggested test and removed the "--" couldn't see anything else that might lead to failure, but we'll see how the CI feels about it, if it doesn't like it please ignore the spam (and my appologies for it) on the PR as I try to work out what the CI wants from me for it to pass as it unfortunately passes locally which makes things hard to track! 

https://github.com/llvm/llvm-project/pull/109907