Fix dropdown bug

The selected option is tracked correctly when scrolling through the
dropdown list via keyboard

Beta

Tabview spelling fix

Chart draw bug

Correct instances of hadler -> handler

When drawing chart lines/points/columns, execution will stay in loop forever when point count > 255.
The loop counter i was set to uint8_t when it should be the same size as point_cnt, uint16_t.

fix warning/error with lv_conf.h option