Revert "net: phy: microchip: force IRQ polling mode for lan88xx"

Revert "net: phy: microchip: force IRQ polling mode for lan88xx"

This reverts commit 853e14cf36f6b16a372444a1eff54a3d7c6c1268 which is
commit 30a41ed32d3088cd0d682a13d7f30b23baed7e93 upstream.

It is reported to cause NFS boot problems on a Raspberry Pi 3b so revert
it from this branch for now.

Cc: Fiona Klute <fiona.klute@gmx.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Sasha Levin <sashal@kernel.org>
Link: https://lore.kernel.org/r/aB6uurX99AZWM9I1@finisterre.sirena.org.uk
Reported-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>