[ALSA] Fix schedule_timeout usage

Use schedule_timeout_{,un}interruptible() instead of
set_current_state()/schedule_timeout() to reduce kernel size.  Also use
human-time conversion functions instead of hard-coded division to avoid
rounding issues.

Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/isa/sb/emu8000_pcm.c

@@ -117,8 +117,7 @@ snd_emu8000_write_wait(emu8000_t *emu, int can_schedule)
 {
 	while ((EMU8000_SMALW_READ(emu) & 0x80000000) != 0) {
 		if (can_schedule) {
-			set_current_state(TASK_INTERRUPTIBLE);
-			schedule_timeout(1);
+			schedule_timeout_interruptible(1);
 			if (signal_pending(current))
 				break;
 		}