thermal: imx_tmu: Clean up all prints

Use dev_(dev, ...) for all printing and debug logging, since this
already includes the device name. Drop device name where duplicate.

Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Andrejs Cainikovs <andrejs.cainikovs@toradex.com>