arm: mvebu: Espressobin: move network setup into a separate function

Currently, Esspresobin switch is being setup directly in last_stage_init()
which makes it hard to add support for any other board to be setup.

So, lets just move the switch setup code to a separate function and call it
if compatible matches, there should be no functional change.

Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/board/Marvell/mvebu_armada-37xx/board.c b/board/Marvell/mvebu_armada-37xx/board.c
index 1471caa..f532486 100644
--- a/board/Marvell/mvebu_armada-37xx/board.c
+++ b/board/Marvell/mvebu_armada-37xx/board.c
@@ -301,14 +301,12 @@
 	return 0;
 }
 
-/* Bring-up board-specific network stuff */
-static int last_stage_init(void)
+static int espressobin_last_stage_init(void)
 {
 	struct udevice *bus;
 	ofnode node;
 
-	if (!CONFIG_IS_ENABLED(DM_MDIO) ||
-	    !of_machine_is_compatible("globalscale,espressobin"))
+	if (!CONFIG_IS_ENABLED(DM_MDIO))
 		return 0;
 
 	node = ofnode_by_compatible(ofnode_null(), "marvell,orion-mdio");
@@ -358,8 +356,17 @@
 
 	return 0;
 }
-EVENT_SPY_SIMPLE(EVT_LAST_STAGE_INIT, last_stage_init);
 
+/* Bring-up board-specific network stuff */
+static int last_stage_init(void)
+{
+
+	if (of_machine_is_compatible("globalscale,espressobin"))
+		return espressobin_last_stage_init();
+
+	return 0;
+}
+EVENT_SPY_SIMPLE(EVT_LAST_STAGE_INIT, last_stage_init);
 #endif
 
 #ifdef CONFIG_OF_BOARD_SETUP