stmmac: rework the code to get the Synopsys ID (v3)

The Synopsys ID is now passed from the MAC core
to the main. This info will be used for managing
the HW cap register (supported in the new GMAC
generations).

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/common.h

@@ -230,6 +230,7 @@ struct mac_device_info {
 	const struct stmmac_dma_ops	*dma;
 	struct mii_regs mii;	/* MII register Addresses */
 	struct mac_link link;
+	unsigned int synopsys_uid;
 };
 
 struct mac_device_info *dwmac1000_setup(void __iomem *ioaddr);