add temporary fix to example 1

I am debugging issue with windows user. I noticed the latest version of
ifx/ifort builds with a different integer type which leads to error:

```
error #6284: There is no matching specific function for this generic function reference.   [TORCH_TENSOR_FROM_ARRAY]
   in_tensors(1) = torch_tensor_from_array(in_data, tensor_layout, torch_kCPU)
-------------------^
```

This can be removed by forcing the integer type to int64

examples/1_SimpleNet/simplenet_infer_fortran.f90

@@ -1,7 +1,7 @@
 program inference
 
    ! Import precision info from iso
-   use, intrinsic :: iso_fortran_env, only : sp => real32
+   use, intrinsic :: iso_fortran_env, only : sp => real32, int64
 
    ! Import our library for interfacing with PyTorch
    use ftorch
@@ -18,7 +18,7 @@ program inference
    real(wp), dimension(5), target :: in_data
    real(wp), dimension(5), target :: out_data
    integer, parameter :: n_inputs = 1
-   integer :: tensor_layout(1) = [1]
+   integer(int64) :: tensor_layout(1) = [1]
 
    ! Set up Torch data structures
    ! The net, a vector of input tensors (in this case we only have one), and the output tensor