net: stmmac: qcom-ethqos: use phy interface mode for inband

net: stmmac: qcom-ethqos: use phy interface mode for inband

qcom-ethqos currently forces inband to be enabled for the Cisco SGMII
speeds (1G, 100M and 10M) but not for 2500BASE-X (2.5G).

Rather than using the speed to determine the forced inband state, use
phylink's PHY interface mode which will switch between SGMII for the
10M, 100M and 1G speeds, and 2500BASE-X for 2.5G.

Reviewed-by: Mohd Ayaan Anwar <mohd.anwar@oss.qualcomm.com>
Tested-by: Mohd Ayaan Anwar <mohd.anwar@oss.qualcomm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/E1vuSL5-0000000AScX-2wuM@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>