[ALSA] Move OSS-specific hw_params helper to snd-pcm-oss module

Move EXPORT_SYMBOL()s to places adjacent to functions/variables.
Also move OSS-specific hw_params helper functions to pcm_oss.c.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/pcm_params.h b/include/sound/pcm_params.h
index e3bebd9..85cf1cf 100644
--- a/include/sound/pcm_params.h
+++ b/include/sound/pcm_params.h
@@ -22,18 +22,14 @@
  *
  */
 
-extern int snd_pcm_hw_param_mask(struct snd_pcm_substream *pcm, struct snd_pcm_hw_params *params,
-				 snd_pcm_hw_param_t var, const struct snd_mask *val);
-extern unsigned int snd_pcm_hw_param_value_min(const struct snd_pcm_hw_params *params,
-					       snd_pcm_hw_param_t var, int *dir);
-extern unsigned int snd_pcm_hw_param_value_max(const struct snd_pcm_hw_params *params,
-					       snd_pcm_hw_param_t var, int *dir);
-extern int _snd_pcm_hw_param_min(struct snd_pcm_hw_params *params,
-				 snd_pcm_hw_param_t var, unsigned int val, int dir);
-extern int _snd_pcm_hw_param_setinteger(struct snd_pcm_hw_params *params,
-					snd_pcm_hw_param_t var);
-extern int _snd_pcm_hw_param_set(struct snd_pcm_hw_params *params,
-				 snd_pcm_hw_param_t var, unsigned int val, int dir);
+int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm, 
+			   struct snd_pcm_hw_params *params,
+			   snd_pcm_hw_param_t var, int *dir);
+int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm, 
+			  struct snd_pcm_hw_params *params,
+			  snd_pcm_hw_param_t var, int *dir);
+int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
+			   snd_pcm_hw_param_t var, int *dir);
 
 #define SNDRV_MASK_BITS	64	/* we use so far 64bits only */
 #define SNDRV_MASK_SIZE	(SNDRV_MASK_BITS / 32)