Add get_device_id method to SyclDevice and permit construction of SyclDevice from result id

This enables users to convert from a dldevice ID to a SYCL device, i.e.,

```
import dpctl
import dpctl.tensor as dpt

x = dpt.arange(10)
dldev = x.__dlpack_device__()
dev = dpctl.SyclDevice(dldev[1])
print(dev.get_device_id() == dldev[1])
```

Author: ndgrigorian

dpctl/_sycl_device.pyx

@@ -355,6 +355,16 @@ cdef class SyclDevice(_SyclDevice):
                 raise SyclDeviceCreationError(
                     "Could not create a SyclDevice from _SyclDevice instance"
                 )
+        elif type(arg) is int:
+            string = bytes(str(arg), "utf-8")
+            filter_c_str = string
+            DSRef = DPCTLFilterSelector_Create(filter_c_str)
+            ret = self._init_from_selector(DSRef)
+            if ret == -1:
+                raise SyclDeviceCreationError(
+                    "Could not create a SyclDevice from device id "
+                    "'{dev_id}'".format(dev_id=arg)
+                )
         elif arg is None:
             DSRef = DPCTLDefaultSelector_Create()
             ret = self._init_from_selector(DSRef)
@@ -1950,9 +1960,7 @@ cdef class SyclDevice(_SyclDevice):
 
     cdef int get_overall_ordinal(self):
         """ If this device is a root ``sycl::device``, returns the ordinal
-        position of this device in the vector ``sycl::device::get_devices()``
-        filtered to contain only devices with the same backend as this
-        device.
+        position of this device in the vector ``sycl::device::get_devices()``.
 
         Returns -1 if the device is a sub-device, or the device could not
         be found in the vector.
@@ -2045,6 +2053,18 @@ cdef class SyclDevice(_SyclDevice):
                 else:
                     return str(relId)
 
+    def get_device_id(self):
+        cdef int dev_id = -1
+
+        if self.parent_device:
+            raise TypeError("This SyclDevice is not a root device")
+
+        dev_id = self.get_overall_ordinal()
+        if dev_id < 0:
+            raise ValueError
+        return dev_id
+
+
 cdef api DPCTLSyclDeviceRef SyclDevice_GetDeviceRef(SyclDevice dev):
     """
     C-API function to get opaque device reference from