net: ethernet: stmmac: add support of Synopsys 3.50a MAC IP

Adds support of Synopsys 3.50a MAC IP in stmmac driver.
Acked-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Tested-by: NMaxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: NAlexandre TORGUE <alexandre.torgue@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

@@ -265,6 +265,7 @@ stmmac_probe_config_dt(struct platform_device *pdev, const char **mac)
 	 * once needed on other platforms.
 	 */
 	if (of_device_is_compatible(np, "st,spear600-gmac") ||
+		of_device_is_compatible(np, "snps,dwmac-3.50a") ||
 		of_device_is_compatible(np, "snps,dwmac-3.70a") ||
 		of_device_is_compatible(np, "snps,dwmac")) {
 		/* Note that the max-frame-size parameter as defined in the