tools include UAPI: Sync sound/asound.h copy with the kernel sources

Picking the changes from:

  69ab6f5b ("ALSA: Remove some left-over license text in include/uapi/sound/")

Which entails no changes in the tooling side as it doesn't introduce new
SNDRV_PCM_IOCTL_ ioctls.

To silence this perf tools build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/sound/asound.h' differs from latest version at 'include/uapi/sound/asound.h'
  diff -u tools/include/uapi/sound/asound.h include/uapi/sound/asound.h

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>