net/fman: add a fm_enable_port function

This can be useful if one wants to disable an interface in u-boot
because u-boot should not manage it but then later reenable it for FDT
fixing or if the kernel uses this interface.

Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
[York Sun: fix conflict in fm_eth.h]
Acked-by: York Sun <yorksun@freescale.com>
diff --git a/drivers/net/fm/fm.h b/drivers/net/fm/fm.h
index 5f197a9..3ec49a4 100644
--- a/drivers/net/fm/fm.h
+++ b/drivers/net/fm/fm.h
@@ -99,6 +99,7 @@
 int fm_eth_initialize(struct ccsr_fman *reg, struct fm_eth_info *info);
 phy_interface_t fman_port_enet_if(enum fm_port port);
 void fman_disable_port(enum fm_port port);
+void fman_enable_port(enum fm_port port);
 
 struct fsl_enet_mac {
 	void *base; /* MAC controller registers base address */