[mlir, win] Mark several MLRI tests as unsupported on system-windows

[stella.stamenova]

Summary

They are currently marked as unsupported when windows is part of the triple, but they actually fail when they are run on Windows, so they are unsupported on system-windows

[jpienaar]

Thanks

mlir/test/mlir-reduce/dce-test.mlir

-// UNSUPPORTED: -windows-
+// UNSUPPORTED: system-windows
 // RUN: mlir-reduce %s -test %S/failure-test.sh -pass-test DCE | FileCheck %s
 // This input should be reduced by the pass pipeline so that only
 // the @simple1 function remains as the other functions should be
 // removed by the dead code elimination pass.
 // CHECK-LABEL: func @simple1(%arg0: i1, %arg1: memref<2xf32>, %arg2: memref<2xf32>) {
 
 // CHECK-NOT: func @dead_nested_function
 func @dead_private_function() attributes { sym_visibility = "private" }
 
 // CHECK-NOT: func @dead_nested_function
 func @dead_nested_function() attributes { sym_visibility = "nested" }
 
 func @simple1(%arg0: i1, %arg1: memref<2xf32>, %arg2: memref<2xf32>) {
   "test.crashOp" () : () -> ()
   return
 }

mlir/test/mlir-reduce/multiple-function.mlir

-// UNSUPPORTED: -windows-
+// UNSUPPORTED: system-windows
 // RUN: mlir-reduce %s -test %S/failure-test.sh -pass-test function-reducer | FileCheck %s
 // This input should be reduced by the pass pipeline so that only 
 // the @simple5 function remains as this is the shortest function 
 // containing the interesting behavior.
 
 // CHECK-NOT: func @simple1() {
 func @simple1() {
   return

mlir/test/mlir-reduce/simple-test.mlir

-// UNSUPPORTED: -windows-
+// UNSUPPORTED: system-windows
 // RUN: mlir-reduce %s -test %S/test.sh -pass-test function
 
 func @simple1(%arg0: i1, %arg1: memref<2xf32>, %arg2: memref<2xf32>) {
   cond_br %arg0, ^bb1, ^bb2
 ^bb1:
   br ^bb3(%arg1 : memref<2xf32>)
 ^bb2:
   %0 = alloc() : memref<2xf32>
   br ^bb3(%0 : memref<2xf32>)
 ^bb3(%1: memref<2xf32>):
   return
 }