pinctrl: mvebu: add driver for Armada CP110 pinctrl

This commit adds a pinctrl driver for the CP110 part of the Marvell
Armada 7K and 8K SoCs. The Armada 7K has a single CP110, where almost all
the MPP pins are available. On the other side, the Armada 8K has two
CP110, and the available MPPs are split between the master CP110 (MPPs 32
to 62) and the slave CP110 (MPPs 0 to 31).

The register interface to control the MPPs is however the same as all
other mvebu SoCs, so we can reuse the common pinctrl-mvebu.c logic.

Signed-off-by: Hanna Hawa <hannah@marvell.com>
Reviewed-by: Shadi Ammouri <shadi@marvell.com>

[updated for mvebu pinctrl and 4.9 changes:
 - converted to simple_mmio
 - converted to syscon/regmap
 - removed unimplemented .remove function
 - dropped DTS changes
 - defered gpio ranges to DT
 - fixed warning
 - properly set soc->nmodes
 -- rmk]
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

[ add missing MPP[61:56] function 14 (SDIO)
-- Konstantin Porotchkin]
Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>

[ allow to properly register more then one instance of this driver
-- Grzegorz Jaszczyk]
Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com>

[ - rebased on 4.12-rc1
  - fixed the 80 character limit for mvebu_mpp_mode array
  - aligned the compatible name on the ones already used
  - fixed the MPP table for CP110: some MPP are not available on Armada 7K
-- Gregory CLEMENT]
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>