[llvm] [mlir] [mlir] Add config for PDL (PR #69927)

[Jacques Pienaar via llvm-commits]

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@@ -3312,6 +3312,7 @@ auto ConversionTarget::getOpInfo(OperationName op) const
   return std::nullopt;
 }
 
+#if MLIR_ENABLE_PDL
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jpienaar wrote:

This one is trickier as the parts here depend on ConversionPatternRewriterImpl, so would result in weird library split.

https://github.com/llvm/llvm-project/pull/69927