[mlir][memref] Rename MemRef directories and files. NFC. (#102337)

This PR renames the `MemRef` integration test directory for and the
`DecomposeMemref.s.cpp` so that they can be found when doing a
case-sensitive search on file paths.

Author: angelz913

mlir/lib/Dialect/GPU/CMakeLists.txt

@@ -28,7 +28,7 @@ add_mlir_dialect_library(MLIRGPUTransforms
   Transforms/AllReduceLowering.cpp
   Transforms/AsyncRegionRewriter.cpp
   Transforms/BufferDeallocationOpInterfaceImpl.cpp
-  Transforms/DecomposeMemrefs.cpp
+  Transforms/DecomposeMemRefs.cpp
   Transforms/EliminateBarriers.cpp
   Transforms/GlobalIdRewriter.cpp
   Transforms/KernelOutlining.cpp

mlir/lib/Dialect/GPU/Transforms/DecomposeMemrefs.cpp renamed to mlir/lib/Dialect/GPU/Transforms/DecomposeMemRefs.cpp

@@ -1,4 +1,4 @@
-//===- DecomposeMemrefs.cpp - Decompose memrefs pass implementation -------===//
+//===- DecomposeMemRefs.cpp - Decompose memrefs pass implementation -------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.