net: Fix warning when including netdev.h on DM systems

If the DM_ETH is enabled and netdev.h is included somewhere, the
struct eth_device may not be defined, yet it is used in the header
file as an argument to fecmxc_register_mii_postcall. Add forward
declaration to remove the warning.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Joe Hershberger <joe.hershberger@ni.com>

diff --git a/include/netdev.h b/include/netdev.h
index 68a3fce..f2d21c4 100644 (file)
--- a/include/netdev.h
+++ b/include/netdev.h
@@ -125,6 +125,7 @@ int fec_probe(bd_t *bd, int dev_id, uint32_t base_addr,
 /*
  * Allow FEC to fine-tune MII configuration on boards which require this.
  */
+struct eth_device;
 int fecmxc_register_mii_postcall(struct eth_device *dev, int (*cb)(int));
 #endif