armv8: ls1043ardb: invert irq pin polarity for AQR105 PHY

To use AQR105 PHY's interrupt, we need to invert the IRQ pin polarity
by setting relative bit in SCFG_INTPCR register, because AQR105
interrupt is low active but GIC accepts high active.

Signed-off-by: Shaohui Xie <Shaohui.Xie@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>