nfc: Reduce nfc_evt_transaction params length to 0

According to etsi 102 622 chapter 11.2.2.4 EVT_TRANSACTION,
the nfc_evt_transaction parameters can be 0 up to 255 byte long.
Signed-off-by: NChristophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

include/net/nfc/nfc.h

@@ -157,7 +157,7 @@ struct nfc_evt_transaction {
 	u32 aid_len;
 	u8 aid[NFC_MAX_AID_LENGTH];
 	u8 params_len;
-	u8 params[NFC_MAX_PARAMS_LENGTH];
+	u8 params[0];
 } __packed;
 
 struct nfc_genl_data {