Add a small "hdajacksensetest" helper

I previously had a small python script doing the same thing,
but it depended on hda-analyzer, which always breaks when something
new is added to the codec proc file.

I got tired and rewrote it as a small C program instead, which I
hope will be a useful addition to alsa-tools.

Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>