pinctrl: armada-cp110 - fix MPP54/MPP55 functions

The function name is used for selecting MPP functionality and
should be unique within function names of the same pin.
This patch fixes function names for MPP54 and MPP55 that
have two different functions named the same.

Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>
Link: https://lore.kernel.org/r/20210216113118.17484-3-kostap@marvell.com


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