gpio/mmc/of: Respect polarity in the device tree

The device tree bindings for the MMC card detect and
write protect lines specify that these should be active
low unless "cd-inverted" or "wp-inverted" has been
specified.

However that is not how the kernel code has worked. It
has always respected the flags passed to the phandle in
the device tree, but respected the "cd-inverted" and
"wp-inverted" flags such that if those are set, the
polarity will be the inverse of that specified in the
device tree.

Switch to behaving like the old code did and fix the
regression.

Fixes: 81c85ec1

 ("gpio: OF: Parse MMC-specific CD and WP properties")
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>