[lld] [ELF] Merge verdefIndex into versionId. NFC (PR #72208)

[Peter Smith via llvm-commits]

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@@ -313,11 +313,12 @@ class Symbol {
   uint32_t auxIdx;
   uint32_t dynsymIndex;
 
-  // This field is a index to the symbol's version definition.
-  uint16_t verdefIndex;
-
-  // Version definition index.
+  // For a Defined symbol, this represents the Verdef index (VER_NDX_LOCAL,
+  // VER_NDX_GLOBAL, or a named version). For a SharedSymbol, this represents
+  // the Verdef index within the input DSO, which will be converted to a Verneed
+  // index in the output.
   uint16_t versionId;
+  uint8_t versionScriptAssigned : 1;
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smithp35 wrote:

Would it be better to move this below thunkAccessed as I think that would mean that bit could be part of the uint8_t container (I count 7 bits so far). Or is the intention to start a new container.

https://github.com/llvm/llvm-project/pull/72208