pinctrl: imx: Fix compilation with DEBUG enabled

This became broken with converting the pinmux arrays into struct
types. While at it replace the preprocessor magic with a simple
dev_dbg.

Reported-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>