[ALSA] fix comments in sound/core.h

Two sentences seem to be spliced into one in comment, fix that and fix
english. Also fix codingstyle.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/core.h b/include/sound/core.h
index 4fc0235..356659d 100644
--- a/include/sound/core.h
+++ b/include/sound/core.h
@@ -310,7 +310,7 @@
 int snd_card_file_remove(struct snd_card *card, struct file *file);
 
 #ifndef snd_card_set_dev
-#define snd_card_set_dev(card,devptr) ((card)->dev = (devptr))
+#define snd_card_set_dev(card, devptr) ((card)->dev = (devptr))
 #endif
 
 /* device.c */
@@ -373,7 +373,7 @@
  * snd_printd - debug printk
  * @fmt: format string
  *
- * Compiled only when Works like snd_printk() for debugging purpose.
+ * Works like snd_printk() for debugging purposes.
  * Ignored when CONFIG_SND_DEBUG is not set.
  */
 #define snd_printd(fmt, args...) \
@@ -417,7 +417,7 @@
  * snd_printdd - debug printk
  * @format: format string
  *
- * Compiled only when Works like snd_printk() for debugging purpose.
+ * Works like snd_printk() for debugging purposes.
  * Ignored when CONFIG_SND_DEBUG_DETECT is not set.
  */
 #define snd_printdd(format, args...) snd_printk(format, ##args)