[ALSA] Reverted last patch for SNDCTL_DSP_GETOPTR fix & possible overflow fix

ALSA<-OSS emulation
This reverts the last patch which wrongly mixes bytes and frames.
The real culprit might be the 32-bit overflow, so the return expression uses
64-bit values now in snd_pcm_oss_bytes().

Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c
index 6f90dbb..a293982 100644
--- a/sound/core/oss/pcm_oss.c
+++ b/sound/core/oss/pcm_oss.c
@@ -124,13 +124,12 @@
 
 static long snd_pcm_oss_bytes(snd_pcm_substream_t *substream, long frames)
 {
-	long bytes = 0;
 	snd_pcm_runtime_t *runtime = substream->runtime;
 	snd_pcm_uframes_t buffer_size = snd_pcm_lib_buffer_bytes(substream);
-	bytes = frames_to_bytes(runtime, frames);
+	frames = frames_to_bytes(runtime, frames);
 	if (buffer_size == runtime->oss.buffer_bytes)
-		return bytes;
-	return (runtime->oss.buffer_bytes * frames) / buffer_size;
+		return frames;
+	return (long)(((int64_t)runtime->oss.buffer_bytes * (int64_t)frames) / (int64_t)buffer_size);
 }
 
 static long snd_pcm_alsa_frames(snd_pcm_substream_t *substream, long bytes)