Destroys the request handle and frees its resources.
PPS_REQUEST pRequest
An opaque handle to a request created by the PsRequestCreate function.
If the function succeeds, the return value is PULSE_STATUS_SUCCESS.
If it fails, it returns one of the PULSE_STATUS values. Possible return codes include, but are not limited to, the following:
| PULSE_STATUS_INVALID_PARAMETER0xC0000010 | The pRequest parameter is NULL. |
Cancels any pending Pulse API call assigned to this request.