net: phy: meson-gxl: fix interrupt handling in forced mode

This PHY doesn't support a link-up interrupt source. If aneg is enabled
we use the "aneg complete" interrupt for this purpose, but if aneg is
disabled link-up isn't signaled currently.
According to a vendor driver there's an additional "energy detect"
interrupt source that can be used to signal link-up if aneg is disabled.
We can safely ignore this interrupt source if aneg is enabled.

This patch was tested on a TX3 Mini TV box with S905W (even though
boot message says it's a S905D).

This issue has been existing longer, but due to changes in phylib and
the driver the patch applies only from the commit marked as fixed.

Fixes: 84c8f773

 ("net: phy: meson-gxl: remove the use of .ack_callback()")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/04cac530-ea1b-850e-6cfa-144a55c4d75d@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>