Remove Half duplex mode speed capabilities.

commit 03fa5121 upstream.

Since Half Duplex mode has been deprecated by the firmware, driver should
not advertise Half Duplex speed in ethtool support link speed values.

Fixes: 071a0204 ("net: atlantic: A2: half duplex support")
Signed-off-by: Sameer Saurabh <ssaurabh@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Sudarsana Reddy Kalluru <skalluru@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>