greybus: bootrom: Skip setting timeout in failure path of size request
The currently set value of next_request_type in the error path of
gb_bootrom_firmware_size_request() is not correct, as it should have
been NEXT_REQ_FIRMWARE_SIZE for the failure case (as we should be
waiting for another similar request).
But, if an error occurs in gb_bootrom_firmware_size_request(), then the
ES3 bootrom will never be able to recover from it and send another
request. And so there is no point waiting for another request and timing
out.