[OpenMP] Add support for embedding bitcode images in wrapper tool

[jhuber6]

Summary

Summary;
This patch adds support for embedding device images in the linker
wrapper tool. This will be used for performing JIT functionality in the
future.

Depends on D117048

[jhuber6]

Update approach, improve LTO file handling for multiple outputs and don't change the LTO config.

[jhuber6]

Forgot to use hook.

[saiislam]

It seems that this patch along with D117156 and D117246 is giving patch application failed error [https://buildkite.com/llvm-project/diff-checks/builds/82688].
arc patch is also giving the same error.

[jhuber6]

In D117049#3255748, @saiislam wrote:

It seems that this patch along with D117156 and D117246 is giving patch application failed error [https://buildkite.com/llvm-project/diff-checks/builds/82688].
arc patch is also giving the same error.

I think what happened is I didn't include a small fix patch I had locally in the list somewhere which made the diffs not apply. I could probably try to squash them and reapply if it's important.

[jhuber6]

Rework commits.

[jhuber6]

Removing clang flag because LTO won't be supported when these land.

[tianshilei1992]

I'm gonna accept it for now to make it in 14. We can always come back later if we see anything wrong.