[MLIR] Apply clang-tidy fixes for llvm-qualified-auto in MPIToLLVM.cpp (NFC)

GitOrigin-RevId: 9ee1f159dccbee1e19ab7584e678af9be1054e2d
diff --git a/lib/Conversion/MPIToLLVM/MPIToLLVM.cpp b/lib/Conversion/MPIToLLVM/MPIToLLVM.cpp
index aa47e39..16ef11a 100644
--- a/lib/Conversion/MPIToLLVM/MPIToLLVM.cpp
+++ b/lib/Conversion/MPIToLLVM/MPIToLLVM.cpp
@@ -272,7 +272,7 @@
 
   Value getCommWorld(const Location loc,
                      ConversionPatternRewriter &rewriter) override {
-    auto context = rewriter.getContext();
+    auto *context = rewriter.getContext();
     // get external opaque struct pointer type
     auto commStructT =
         LLVM::LLVMStructType::getOpaque("ompi_communicator_t", context);
@@ -324,7 +324,7 @@
     else
       assert(false && "unsupported type");
 
-    auto context = rewriter.getContext();
+    auto *context = rewriter.getContext();
     // get external opaque struct pointer type
     auto typeStructT =
         LLVM::LLVMStructType::getOpaque("ompi_predefined_datatype_t", context);
@@ -383,7 +383,7 @@
       op = "ompi_mpi_replace";
       break;
     }
-    auto context = rewriter.getContext();
+    auto *context = rewriter.getContext();
     // get external opaque struct pointer type
     auto opStructT =
         LLVM::LLVMStructType::getOpaque("ompi_predefined_op_t", context);