ALSA: core: Fix kernel-doc warnings

Several lines in sound/core.h get the kernel-doc warnings like

  ./include/sound/core.h:323: warning: No description found for parameter '...'

where we use define like foo(x, args...) and "args" isn't mentioned in
the comments.  As an easy workaround, use simple __VA_ARGS__ for VLA
in macros.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

include/sound/core.h

@@ -308,8 +308,8 @@ __printf(4, 5)
 void __snd_printk(unsigned int level, const char *file, int line,
 		  const char *format, ...);
 #else
-#define __snd_printk(level, file, line, format, args...) \
-	printk(format, ##args)
+#define __snd_printk(level, file, line, format, ...) \
+	printk(format, ##__VA_ARGS__)
 #endif
 
 /**
@@ -319,8 +319,8 @@ void __snd_printk(unsigned int level, const char *file, int line,
  * Works like printk() but prints the file and the line of the caller
  * when configured with CONFIG_SND_VERBOSE_PRINTK.
  */
-#define snd_printk(fmt, args...) \
-	__snd_printk(0, __FILE__, __LINE__, fmt, ##args)
+#define snd_printk(fmt, ...) \
+	__snd_printk(0, __FILE__, __LINE__, fmt, ##__VA_ARGS__)
 
 #ifdef CONFIG_SND_DEBUG
 /**
@@ -330,10 +330,10 @@ void __snd_printk(unsigned int level, const char *file, int line,
  * Works like snd_printk() for debugging purposes.
  * Ignored when CONFIG_SND_DEBUG is not set.
  */
-#define snd_printd(fmt, args...) \
-	__snd_printk(1, __FILE__, __LINE__, fmt, ##args)
-#define _snd_printd(level, fmt, args...) \
-	__snd_printk(level, __FILE__, __LINE__, fmt, ##args)
+#define snd_printd(fmt, ...) \
+	__snd_printk(1, __FILE__, __LINE__, fmt, ##__VA_ARGS__)
+#define _snd_printd(level, fmt, ...) \
+	__snd_printk(level, __FILE__, __LINE__, fmt, ##__VA_ARGS__)
 
 /**
  * snd_BUG - give a BUG warning message and stack trace
@@ -383,8 +383,8 @@ static inline bool snd_printd_ratelimit(void) { return false; }
  * Works like snd_printk() for debugging purposes.
  * Ignored when CONFIG_SND_DEBUG_VERBOSE is not set.
  */
-#define snd_printdd(format, args...) \
-	__snd_printk(2, __FILE__, __LINE__, format, ##args)
+#define snd_printdd(format, ...) \
+	__snd_printk(2, __FILE__, __LINE__, format, ##__VA_ARGS__)
 #else
 __printf(1, 2)
 static inline void snd_printdd(const char *format, ...) {}