[mlir] Remove duplicate includes (NFC)

Identified with readability-duplicate-include.

Author: kazutakahirata

mlir/lib/Dialect/SparseTensor/Transforms/SparsificationAndBufferizationPass.cpp

@@ -22,7 +22,6 @@
 #include "mlir/Dialect/Linalg/IR/Linalg.h"
 #include "mlir/Dialect/SCF/IR/SCF.h"
 #include "mlir/Dialect/SparseTensor/IR/SparseTensor.h"
-#include "mlir/Dialect/SparseTensor/Transforms/Passes.h"
 #include "mlir/Dialect/Vector/IR/VectorOps.h"
 #include "mlir/Pass/PassManager.h"
 #include "mlir/Transforms/Passes.h"

mlir/test/lib/Dialect/Test/TestDialect.cpp

@@ -37,7 +37,6 @@
 #include "llvm/Support/Base64.h"
 #include "llvm/Support/Casting.h"
 
-#include "mlir/Dialect/Arith/IR/Arith.h"
 #include "mlir/Dialect/DLTI/DLTI.h"
 #include "mlir/Interfaces/FoldInterfaces.h"
 #include "mlir/Reducer/ReductionPatternInterface.h"