pinctrl: sprd: Use the correct pin output configuration

The Spreadtrum pin controller did not supply registers to set high level
or low level for output mode, instead we should let the pin controller
current configuration drive values on the line. So we should use the
PIN_CONFIG_OUTPUT_ENABLE configuration to enable or disable the output
mode.

[Baolin Wang changes the commit message]
Fixes: 41d32cfc ("pinctrl: sprd: Add Spreadtrum pin control driver")
Signed-off-by: Linhua Xu <linhua.xu@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/8a6f91b49c17beb218e46b23084f59a7c7260f86.1585124562.git.baolin.wang7@gmail.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>