adc: adc_intel_quark_d2000: Pass 0 for IRQ Priority
adc: adc_intel_quark_d2000: Pass 0 for IRQ Priority

The Interrupt Controller on the Quark D2000 doesn't support irq priority
to just pass 0 in the for the priority instead of CONFIG_ADC_0_IRQ_PRI.

Signed-off-by: Kumar Gala <a5e5248af4cd4f0ed8c515f61d40a6e2db46a66e@linaro.org>

nashif/zephyr,Vudentz/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,GiulianoFranchetto/zephyr,finikorg/zephyr,ldts/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,Vudentz/zephyr,explora26/zephyr,punitvara/zephyr,galak/zephyr,finikorg/zephyr,Vudentz/zephyr,punitvara/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,finikorg/zephyr,Vudentz/zephyr,punitvara/zephyr,Vudentz/zephyr,ldts/zephyr,ldts/zephyr,finikorg/zephyr,galak/zephyr,punitvara/zephyr,zephyrproject-rtos/zephyr,ldts/zephyr,galak/zephyr,explora26/zephyr,GiulianoFranchetto/zephyr,nashif/zephyr,GiulianoFranchetto/zephyr,explora26/zephyr,punitvara/zephyr,explora26/zephyr,explora26/zephyr,GiulianoFranchetto/zephyr,nashif/zephyr,ldts/zephyr,zephyrproject-rtos/zephyr