04c84ed158
This change is for all boards with a sam0 cpu. This cpu just has one ADC. It is unnecessary to have defines with ADC_0_ prefix as if multiple ADCs are possible. Some defines were not used, such as ADC_0_EN, ADC_0_CHANNELS, ADC_MAX_CHANNELS, ADC_0_CLK_SOURCE, ADC_0_CHANNELS Change all ADC_0_ prefixes to ADC_