ALSA: hdspm: Drop linux/types.h inclusion in uapi header

The hdspm.h uapi header has been used also from non-Linux or platforms
that don't have linux/*.h.  It was OK in the past because alsa-lib
contained the modified version of this header file, but now it tries
to the verbatim copy, so it broke the build.  This fixes it again.

Link: https://lore.kernel.org/r/20191220153415.2740-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

include/uapi/sound/hdspm.h

@@ -21,8 +21,6 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#include <linux/types.h>
-
 /* Maximum channels is 64 even on 56Mode you have 64playbacks to matrix */
 #define HDSPM_MAX_CHANNELS      64