phy: fix 10/100Mbps operation on 1Gbps-capable links

de1d786 [add support for Xilinx 1000BASE-X phy (GTX)] introduced a
check for the extended status register in order to support
1Gbps-capable PHYs that don't have the 1000BASE-T registers. Since
Extended Status only indicates what the PHY (i.e. the local side) is
capable of, this broke communication with non-1Gbps peers.

Only check the extended status if the 1000BASE-T registers are
actually missing so we don't end up setting speed to 1Gbps even though
the previous test (for the combination of local and peer support for
1Gbps) already indicated we can't do 1Gbps with the current peer.

Signed-off-by: Sascha Silbe <t-uboot@infra-silbe.de>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
net: phy: Set SUPPORTED_1000baseX_Half flag in ESTATUS_1000_XHALF case

Commit de1d786e (add support for Xilinx 1000BASE-X phy (GTX)) introduced the
checking for ESTATUS_1000_XHALF, but it incorrectly sets the
SUPPORTED_1000baseX_Full flag in this case.

Set the SUPPORTED_1000baseX_Half flag instead.

Acked-by: Charles Coldwell <coldwell@gmail.com>
Reviewed-By: Sascha Silbe <t-uboot@infra-silbe.de>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>