lxf: Support version 1 files

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
lxf: Support 16-channel files

Reported, analyzed and tested by Gabriel Gerard.

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
pcm: support 24-bit/32-bit little-endian planar

Used by LXF.

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
lxf: remove deplanarization hack

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
lxf: check the nb_streams instead of relying on padding

Remove the now unneeded stream pointer while at it.

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org