ADC analog airspeed sensor fix.

...as the variable struct adc_msg_s buf_adc was only 8 channel long although pin 15 wrote into channel 10.

by extending the struct to a length of 10 (struct adc_msg_s buf_adc[10];), the adc will now contain all necessary information.
This fix will also ensure that line 1224-1251 are actually executed (they where not before).