kingst-la2016: shuffle code order to follow application perspective

kingst-la2016: shuffle code order to follow application perspective

Sort "set threshold voltage" code blocks into numerical order of voltage
levels for improved readability. It's surprising to find ">= 2.9V" then
"<= -0.4V" and then "between those" at the end.

Move the la2016_has_triggered() routine next to run_state() since both
of them inspect the device's current run state. Closer inspection even
suggests that one is named inappropriately (not renamed in this commit,
to help reviewers).

The purpose of the set_run_mode() routine's argument most probably is
"mode", and not the surprising "fast blinking". Indicators may just be
a byproduct of setting mode to run or halt.

Make the set_defaults() invocation in la2016_init_device() stand out
more perceivably. Don't hide it in a return statement.