ALSA: pcm: Fix sparse warning wrt PCM format type

The PCM format type is with __bitwise, hence it needs the explicit
cast with __force.  It's ugly, but there is a reason for that cost...

This fixes the sparse warning:
  sound/core/oss/pcm_oss.c:1854:55: warning: incorrect type in argument 1 (different base types)
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/core/oss/pcm_oss.c

@@ -1851,7 +1851,7 @@ static int snd_pcm_oss_get_formats(struct snd_pcm_oss_file *pcm_oss_file)
 	format_mask = hw_param_mask_c(params, SNDRV_PCM_HW_PARAM_FORMAT);
 	for (fmt = 0; fmt < 32; ++fmt) {
 		if (snd_mask_test(format_mask, fmt)) {
-			int f = snd_pcm_oss_format_to(fmt);
+			int f = snd_pcm_oss_format_to((__force snd_pcm_format_t)fmt);
 			if (f >= 0)
 				formats |= f;
 		}