nfc: port100: fix using -ERRNO as command type mask

During probing, the driver tries to get a list (mask) of supported
command types in port100_get_command_type_mask() function.  The value
is u64 and 0 is treated as invalid mask (no commands supported).  The
function however returns also -ERRNO as u64 which will be interpret as
valid command mask.

Return 0 on every error case of port100_get_command_type_mask(), so the
probing will stop.

Cc: <stable@vger.kernel.org>
Fixes: 0347a6ab ("NFC: port100: Commands mechanism implementation")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/nfc/port100.c

@@ -1006,11 +1006,11 @@ static u64 port100_get_command_type_mask(struct port100 *dev)
 
 	skb = port100_alloc_skb(dev, 0);
 	if (!skb)
-		return -ENOMEM;
+		return 0;
 
 	resp = port100_send_cmd_sync(dev, PORT100_CMD_GET_COMMAND_TYPE, skb);
 	if (IS_ERR(resp))
-		return PTR_ERR(resp);
+		return 0;
 
 	if (resp->len < 8)
 		mask = 0;