NFC: digital: SENSF_RES excludes RD when SENSF_REQ RC is zero

The check in digital_tg_send_sensf_res() that excludes
the 'RD' field from the SENSF_RES is inverted.  The 'RD'
field should be excluded when the SENSF_REQ 'RC' field
is equal to DIGITAL_SENSF_REQ_RC_NONE instead of when
its not equal.  This is described in section 6.6.2.11
of the NFC Digital Specification.

CC: Thierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

net/nfc/digital_technology.c

@@ -1101,7 +1101,7 @@ static int digital_tg_send_sensf_res(struct nfc_digital_dev *ddev,
 
 	size = sizeof(struct digital_sensf_res);
 
-	if (sensf_req->rc != DIGITAL_SENSF_REQ_RC_NONE)
+	if (sensf_req->rc == DIGITAL_SENSF_REQ_RC_NONE)
 		size -= sizeof(sensf_res->rd);
 
 	skb = digital_skb_alloc(ddev, size);