[llvm] [Offload][NFC] Factor out and rename the `__tgt_offload_entry` struct (PR #123785)

[Joseph Huber via llvm-commits]

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@@ -21,6 +21,16 @@
 namespace llvm {
 namespace offloading {
 
+/// This is the record of an object that just be registered with the offloading
+/// runtime.
+struct EntryTy {
+  void *Address;
+  char *Symbol;
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jhuber6 wrote:

It corresponds to a symbol so I figured it was more descriptive, an add a name if that makes it clearer.

https://github.com/llvm/llvm-project/pull/123785