[clang] [CIR][NFC] Cleanup MissingFeature asserts in RecordLayoutBuilder (PR #161605)

[Andy Kaylor via cfe-commits]

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@@ -296,9 +296,8 @@ void CIRRecordLowering::lower(bool nonVirtualBaseType) {
   }
 
   llvm::stable_sort(members);
-  // TODO: implement clipTailPadding once bitfields are implemented
-  assert(!cir::MissingFeatures::bitfields());
-  assert(!cir::MissingFeatures::recordZeroInit());
+  // TODO: Verify bitfield clipping
+  assert(!cir::MissingFeatures::checkBitfieldClipping());
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andykaylor wrote:

@Andres-Salamanca There are a couple of other cases in the constant ILE handling where bitfield support is needed, which is what led me to consider the markers here. The ILE code was added recently by @mmha and he may have an implementation prepared. He's on vacation this week, but I'll talk to him about it when he gets back.

https://github.com/llvm/llvm-project/pull/161605