alsa: increase max buffer size

Fixes Ticket373

Thanks to llogan for testing
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavdevice/alsa-audio.h

@@ -43,7 +43,7 @@
 
 typedef void (*ff_reorder_func)(const void *, void *, int);
 
-#define ALSA_BUFFER_SIZE_MAX 32768
+#define ALSA_BUFFER_SIZE_MAX 65536
 
 typedef struct {
     AVClass *class;