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/p1023.c b/drivers/net/fm/p1023.c
index 0eaad0f..b25d10a 100644
--- a/drivers/net/fm/p1023.c
+++ b/drivers/net/fm/p1023.c
@@ -34,6 +34,13 @@
 	setbits_be32(&gur->devdisr, port_to_devdisr[port]);
 }
 
+void fman_enable_port(enum fm_port port)
+{
+	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
+
+	clrbits_be32(&gur->devdisr, port_to_devdisr[port]);
+}
+
 phy_interface_t fman_port_enet_if(enum fm_port port)
 {
 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);