pinctrl: mvebu: armada-39x: add support for Armada 395 variant

The Armada 39x SoC family has grown a new variant, the Armada 395,
which sits between the Armada 390 and Armada 398 in terms of
features. This commit adds support for this additional variant to the
Armada 39x pinctrl driver.

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