[mlir] [llvm] fix linking on riscv64 (PR #74167)

[Mehdi Amini via llvm-commits]

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@@ -16,4 +16,6 @@ add_mlir_library(MLIRPass
   LINK_LIBS PUBLIC
   MLIRAnalysis
   MLIRIR
+  PRIVATE
+  ${LLVM_ATOMIC_LIB}
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joker-eph wrote:

Why isn't this part of `add_mlir_library`? Seems a bit random to add this here and there right now.

https://github.com/llvm/llvm-project/pull/74167