[clang] [clang-format] Don't confuse initializer equal signs in for loops (PR #77712)

[Gedare Bloom via cfe-commits]

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@@ -703,7 +703,9 @@ void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun,
 
   if (Current.is(tok::equal) &&
       (State.Line->First->is(tok::kw_for) || Current.NestingLevel == 0) &&
-      CurrentState.VariablePos == 0) {
+      CurrentState.VariablePos == 0 &&
+      (!Previous.Previous ||
+       Previous.Previous->isNot(TT_DesignatedInitializerPeriod))) {
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gedare wrote:

Might need to search further back if the element being initialized is an array.
`  struct { int x[2]; } a[] = { [0].x = {1,1}, [1].x[0] = 42};`


https://github.com/llvm/llvm-project/pull/77712