ARM: OMAP: board-4430sdp: Proper support for TWL6030 PWM LED/Backlight

ARM: OMAP: board-4430sdp: Proper support for TWL6030 PWM LED/Backlight

New PWM drivers are being prepared for twl series which will enable the use
of all PWMs (PWMs and LEDs).
They are implemented as generic PWM drivers to be able to use them for different
purposes.
The current platform code was broken: the leds_pwm driver was not able to pick
up the PWM since the pwm_id was incorrect.

With the other patches we will be able to control the followings:
LCD backlight via pwm-backlight driver
Keypad leds via leds_pwm driver as normal LED
Charging indicator via leds_pwm driver as normal LED

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>