LF-3506-1 net: phy: realteck: add property to disable ALDPS mode

LF-3506-1 net: phy: realteck: add property to disable ALDPS mode

If enable Advance Link Down Power Saving (ALDPS) mode, it will change
crystal/clock behavior, which cause RXC clock stop for dozens to hundreds
of miliseconds. For EQOS, it needs RXC clock to support RX logic, after
this patch, PHY can generate continuous RXC clock during auto-negotiation.
This patch adds property to disable ALDPS mode.

Reviewed-by: Jun Li <jun.li@nxp.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>