pinctrl: pinctrl-imx: free if of_get_parent fails to get the parent node

of_get_parent can return null if no parent node found, so the allocated new_map
should be freed.

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>