net: stmmac: fixed operator typo

This patch fixed operator typo from & to ==.
Due to incorrect operator, the result is incorrect.
Signed-off-by: NByungho An <bh74.an@samsung.com>
Acked-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -788,13 +788,13 @@ static void stmmac_check_pcs_mode(struct stmmac_priv *priv)
 	int interface = priv->plat->interface;
 
 	if (priv->dma_cap.pcs) {
-		if ((interface & PHY_INTERFACE_MODE_RGMII) ||
-		    (interface & PHY_INTERFACE_MODE_RGMII_ID) ||
-		    (interface & PHY_INTERFACE_MODE_RGMII_RXID) ||
-		    (interface & PHY_INTERFACE_MODE_RGMII_TXID)) {
+		if ((interface == PHY_INTERFACE_MODE_RGMII) ||
+		    (interface == PHY_INTERFACE_MODE_RGMII_ID) ||
+		    (interface == PHY_INTERFACE_MODE_RGMII_RXID) ||
+		    (interface == PHY_INTERFACE_MODE_RGMII_TXID)) {
 			pr_debug("STMMAC: PCS RGMII support enable\n");
 			priv->pcs = STMMAC_PCS_RGMII;
-		} else if (interface & PHY_INTERFACE_MODE_SGMII) {
+		} else if (interface == PHY_INTERFACE_MODE_SGMII) {
 			pr_debug("STMMAC: PCS SGMII support enable\n");
 			priv->pcs = STMMAC_PCS_SGMII;
 		}