net: marvell: mvgbe: Set PHY page 0 before phy_connect

net: marvell: mvgbe: Set PHY page 0 before phy_connect

For most Kirkwood boards, the PHY page is already set to page 0
(in register 22) before phy_connect is invoked. But some board like
the Zyxel NSA310S (which uses the network chip MV88E1318S), the PHY page
is not set to page 0. There seems to be some bad data remained in
register 22 when the uclass MVGBE about to invoke phy_connect().

This patch enables the uclass MVGBE to always set the PHY page to 0
before phy_connect.

For reference, please see this discussion:
[RFC PATCH v2] arm: kirkwood: nsa310s: Use Marvell uclass mvgbe
and PHY driver for DM Ethernet.
https://lists.denx.de/pipermail/u-boot/2022-April/480946.html

This patch has been tested with the following Kirkwood boards:

NSA310S (88F6702, network chip MV88E1318S)
Sheevaplug (88F6281, network chip MV88E1318)
Pogo V4 (88F6192, network chip 88E1116R)
GF Home(88F6281, network chip 88E1116R)
Dreamplug (88F6281, network chip MV88E1318)
Dell Kace M300 (88F6282, network chip MV88E1318) - out of tree u-boot

Signed-off-by: Tony Dinh <mibodhi@gmail.com>