[llvm] [ThinLTO] Fix parsing null aliasee in alias summary (PR #169490)

[Teresa Johnson via llvm-commits]

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@@ -73,6 +73,9 @@
 ^31 = flags: 8
 ^32 = blockcount: 1888
 
+; Alias summary with null aliasee.
+^33 = gv: (guid: 32, summaries: (alias: (module: ^0, flags: (linkage: external, visibility: default, notEligibleToImport: 0, live: 0, dsoLocal: 1), aliasee: null)))
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teresajohnson wrote:

To add on to what @Enna1 asked - this should have a corresponding CHECK below to confirm it round trips through bitcode and back as expected.

https://github.com/llvm/llvm-project/pull/169490