net: dsa: bcm_sf2: always select FIXED_PHY

There is no need to do the following:

select FIXED_PHY if NET_DSA_BCM_SF2=y, as this implies that we will not be
able to build and/or run the driver correctly when built as a module,
which is no longer an issue since commit 37e9a69 ("net: phy: export
fixed_phy_register()").

Fixes: 246d7f7 ("net: dsa: add Broadcom SF2 switch driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/Kconfig

@@ -59,7 +59,7 @@ config NET_DSA_BCM_SF2
 	depends on HAS_IOMEM
 	select NET_DSA
 	select NET_DSA_TAG_BRCM
-	select FIXED_PHY if NET_DSA_BCM_SF2=y
+	select FIXED_PHY
 	select BCM7XXX_PHY
 	select MDIO_BCM_UNIMAC
 	---help---