pinctrl: Pass all configs to driver on pin_config_set()

When setting pin configuration in the pinctrl framework, pin_config_set() or
pin_config_group_set() is called in a loop to set one configuration at a time
for the specified pin or group.

This patch 1) removes the loop and 2) changes the API to pass the whole pin
config array to the driver.  It is now up to the driver to loop through the
configs.  This allows the driver to potentially combine configs and reduce the
number of writes to pin config registers.

All c files changed have been build-tested to verify the change compiles and
that the corresponding .o is successfully generated.

Signed-off-by: Sherman Yin <syin@broadcom.com>
Reviewed-by: Christian Daudt <csd@broadcom.com>
Reviewed-by: Matt Porter <matt.porter@linaro.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>