lpc11u35 - Invert led logic to match hardware
lpc11u35 - Invert led logic to match hardware

The lpc11u35 hdk, like the other hdks, has active low leds. This patch
updates the gpio driver to treat these leds as active low, so passing
in the value GPIO_LED_ON to gpio_set_*_led turns the led on rather
than off.

google/DAPLink-port,google/DAPLink-port,google/DAPLink-port,sg-/DAPLink,sg-/DAPLink,google/DAPLink-port,sg-/DAPLink