OMAP4: PMIC: Rename twl6030_codec as twl6040_codec

Correction for chips:
twl6030 is Phoenix Power chip
twl6040 is Phoenix Audio chip

Signed-off-by: Margarita Olaya Cabrera <magi.olaya@ti.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>