ARM: sunxi: Remove left-over cd-inverted property from pcDuino3

Commit 8620f384

 ("dm: sunxi: Linksprite_pcDuino3: Correct polarity
of MMC card detect") claims that the Pcduino3 device tree had an
incorrect polarity for the card detect pin and thus changed the polarity
flag of the cd-gpios from GPIO_ACTIVE_HIGH to GPIO_ACTIVE_LOW.

Actually the DT was correct since according to the mmc binding, a
combination of GPIO_ACTIVE_HIGH + cd-inverted results in an active-low
polarity. But because the U-Boot driver lacks the code to look at the
cd-inverted property (unlike the Linux driver) it interpreted the
polarity of active-high. Thus, after that commit the DT is actually
wrong from the binding/Linux point of view.

To make both Linux and U-Boot interpret the DT in the same way, just
drop the left-over cd-inverted property. I've sent a Linux patch to
switch all sunxi DTs over to not using the cd-inverted property, so
eventually all sunxi boards in U-Boot will be consistent in not using
cd-inverted.

Signed-off-by: Tuomas Tynkkynen <tuomas@tuxera.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>