pinctrl: pxa: pxa2xx: Remove 'pxa2xx_pinctrl_exit()' which is unused and broken

pinctrl: pxa: pxa2xx: Remove 'pxa2xx_pinctrl_exit()' which is unused and broken

Commit 6d33ee7a0534 ("pinctrl: pxa: Use devm_pinctrl_register() for pinctrl registration")
has turned a 'pinctrl_register()' into 'devm_pinctrl_register()' in
'pxa2xx_pinctrl_init()'.
However, the corresponding 'pinctrl_unregister()' call in
'pxa2xx_pinctrl_exit()' has not been removed.

This is not an issue, because 'pxa2xx_pinctrl_exit()' is unused.
Remove it now to avoid some wondering in the future and save a few LoC.

Fixes: 6d33ee7a0534 ("pinctrl: pxa: Use devm_pinctrl_register() for pinctrl registration")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Link: https://lore.kernel.org/r/20200531073716.593343-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>