ktest: Re-arrange the code blocks for better discoverability

Perl, as with most scripting languages, is fairly flexible in how /
where you can define things, and it will (for the most part) do what you
would expect it to do.  This however can lead to situations, like with
ktest, where things get muddled over time.

This pushes the variable definitions back up to the top, followed by
functions, with the main script executables down at the bottom, INSTEAD
of being somewhat mish-mashed together in certain places.  This mostly
has the advantage of making it more obvious where things are initially
defined, what functions are there, and ACTUALLY where the main script
starts executing, and should make this a little more approachable.

Signed-off-by: John 'Warthog9' Hawley (VMware) <warthog9@eaglescrag.net>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>