alsactl: Move asound.state location to /var/lib/alsa

alsactl: Move asound.state location to /var/lib/alsa

.... and add configure switch for it.

/etc might be on a read-only partition which is not suitable for dynamic
data such as the mixer settings. Hence move the location of asound.state
to /var/lib.

This is based on a patch from Ubuntu/Debian which hardcoded the pah in
/var/lib.

Signed-off-by: Lennart Poettering <mznyfn@0pointer.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>