arm: sunxi: Reduce inrush current on Olimex OLinuXino-A20-Lime2

The lime2 features a too large capacitor on the LDO3 output, which
causes the PMIC to shutdown when enabling power. To be able to still
boot up however, we must gradually enable power on LDO3 for this board.

We do this by enabling both the inrush quirk and the maximum slope the
AXP209 supports.

Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Priit Laes <plaes@plaes.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>