omap3evm: eth: Include functions only when necessary

These functions are not required when CONFIG_CMD_NET
is not defined:
  - setup_net_chip()
  - reset_net_chip()
  - board_eth_init()

This patch wraps them in #ifdef CONFIG_CMD_NET...#endif

Signed-off-by: Sanjeev Premi <premi@ti.com>
Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
diff --git a/board/ti/evm/evm.c b/board/ti/evm/evm.c
index 2c95fae..30c1c57 100644
--- a/board/ti/evm/evm.c
+++ b/board/ti/evm/evm.c
@@ -153,6 +153,7 @@
 	MUX_EVM();
 }
 
+#ifdef CONFIG_CMD_NET
 /*
  * Routine: setup_net_chip
  * Description: Setting up the configuration GPMC registers specific to the
@@ -219,3 +220,4 @@
 #endif
 	return rc;
 }
+#endif /* CONFIG_CMD_NET */