[llvm] [Offload] Erase entries from JIT cache when program is destroyed (PR #148847)

[Ross Brunton via llvm-commits]

================
@@ -285,8 +285,8 @@ JITEngine::compile(const __tgt_device_image &Image,
 
   // Check if we JITed this image for the given compute unit kind before.
   ComputeUnitInfo &CUI = ComputeUnitMap[ComputeUnitKind];
-  if (__tgt_device_image *JITedImage = CUI.TgtImageMap.lookup(&Image))
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RossBrunton wrote:

The data Image points to happens to be inside `ol_program_impl_t`, but something similar to this:

```c++
Image *MyImage = new Image();
delete MyImage;
Image *MyImage2 = new Image();
// MyImage may equal MyImage2
```

https://github.com/llvm/llvm-project/pull/148847