am335x_evm: enable SMSC PHY driver

Beaglebone uses SMSC PHY which works incorrectly with generic PHY
driver so enable SMSC PHY driver to fix networking problems on
Beaglebone.

Signed-off-by: Ilya Yanok <ilya.yanok@cogentembedded.com>

include/configs/am335x_evm.h

@@ -242,5 +242,6 @@
 #define CONFIG_NET_MULTI
 #define CONFIG_PHY_GIGE
 #define CONFIG_PHYLIB
+#define CONFIG_PHY_SMSC
 
 #endif	/* ! __CONFIG_AM335X_EVM_H */