net: ethernet: adi: adin1110: Fix some error handling path in adin1110_read_fifo()

If 'frame_size' is too small or if 'round_len' is an error code, it is
likely that an error code should be returned to the caller.

Actually, 'ret' is likely to be 0, so if one of these sanity checks fails,
'success' is returned.

Return -EINVAL instead.

Fixes: bc93e19 ("net: ethernet: adi: Add ADIN1110 support")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://patch.msgid.link/8ff73b40f50d8fa994a454911b66adebce8da266.1727981562.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: tititiou36

drivers/net/ethernet/adi/adin1110.c

@@ -318,11 +318,11 @@ static int adin1110_read_fifo(struct adin1110_port_priv *port_priv)
 	 * from the  ADIN1110 frame header.
 	 */
 	if (frame_size < ADIN1110_FRAME_HEADER_LEN + ADIN1110_FEC_LEN)
-		return ret;
+		return -EINVAL;
 
 	round_len = adin1110_round_len(frame_size);
 	if (round_len < 0)
-		return ret;
+		return -EINVAL;
 
 	frame_size_no_fcs = frame_size - ADIN1110_FRAME_HEADER_LEN - ADIN1110_FEC_LEN;
 	memset(priv->data, 0, ADIN1110_RD_HEADER_LEN);