[spirv] NFC: rename test files and sort tests inside

PiperOrigin-RevId: 282132339
Change-Id: I0e4bf36020feddfefa308a680b45453e2f27faf0
diff --git a/third_party/mlir/include/mlir/Dialect/SPIRV/SPIRVLowering.h b/third_party/mlir/include/mlir/Dialect/SPIRV/SPIRVLowering.h
index 56182ae..417d0e1 100644
--- a/third_party/mlir/include/mlir/Dialect/SPIRV/SPIRVLowering.h
+++ b/third_party/mlir/include/mlir/Dialect/SPIRV/SPIRVLowering.h
@@ -15,7 +15,7 @@
 // limitations under the License.
 // =============================================================================
 //
-// Defines, utilities and base classes to use while targeting SPIR-V dialect.
+// Defines utilities to use while targeting SPIR-V dialect.
 //
 //===----------------------------------------------------------------------===//