allow invocation of binaries without .exe extension on Windows (llv…

…m#1266)

Signed-off-by: Ian Bearman <ianb@microsoft.com>

Co-authored-by: Tung D. Le <tung@jp.ibm.com>

test/mlir/driver/windows/check_verbosity.mlir

@@ -1,9 +1,9 @@
 // RUN: onnx-mlir -v %s 2>&1 |  FileCheck %s
 
 // REQUIRES: system-windows
-// CHECK:      opt.exe {{.*}} -o {{.*}}check_verbosity.bc 
-// CHECK-NEXT: llc.exe {{.*}} -filetype=obj {{.*}} -o {{.*}}check_verbosity.obj {{.*}}check_verbosity.bc 
-// CHECK-NEXT: cl.exe {{.*}}check_verbosity.obj /Fe:{{.*}}check_verbosity.dll {{.*}}
+// CHECK:      opt{{(\.exe)?}} {{.*}} -o {{.*}}check_verbosity.bc
+// CHECK-NEXT: llc{{(\.exe)?}} {{.*}} -filetype=obj {{.*}} -o {{.*}}check_verbosity.obj {{.*}}check_verbosity.bc
+// CHECK-NEXT: cl{{(\.exe)?}} {{.*}}check_verbosity.obj /Fe:{{.*}}check_verbosity.dll {{.*}}
 module  {
   func @main_graph(%arg0: tensor<1x1xf32>, %arg1: tensor<1x1xf32>) -> tensor<1x1xf32> {
     %0 = "onnx.MatMul"(%arg0, %arg1) : (tensor<1x1xf32>, tensor<1x1xf32>) -> tensor<1x1xf32>