net: ethernet: broadcom: Drop dependency on OF

Both BCMGENET and SYSTEMPORT build just fine with CONFIG_OF=n, we do have a
dependency on HAS_IOMEM that was not being reflected for SYSTEMPORT so add
that.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/Kconfig

@@ -61,7 +61,7 @@ config BCM63XX_ENET
 
 config BCMGENET
 	tristate "Broadcom GENET internal MAC support"
-	depends on OF && HAS_IOMEM
+	depends on HAS_IOMEM
 	select MII
 	select PHYLIB
 	select FIXED_PHY
@@ -181,7 +181,7 @@ config BGMAC_PLATFORM
 
 config SYSTEMPORT
 	tristate "Broadcom SYSTEMPORT internal MAC support"
-	depends on OF
+	depends on HAS_IOMEM
 	depends on NET_DSA || !NET_DSA
 	select MII
 	select PHYLIB