alsa-mixer: Add more jack detection for Headset mic path
On some machines which has a headset jack, the headset mic does not have its own
jack detection. Then we can look at the headphone jack to get some indication:
We know that if the headphone is unplugged, so is the headset mic. The opposite
is not guaranteed since the user might have plugged in a headphone, not a headset.
Also, there exist multi-function jacks which support both Headphone, Mic in headphone jack
and Headset Mic. In this case the jack name will be "Headphone Mic", not "Headphone", so
we need to include this name too.
Signed-off-by: David Henningsson <david.henningsson@canonical.com>