ALSA: core: Use ktime_get_ts()

do_posix_clock_monotonic_gettime() is a leftover from the initial
posix timer implementation which maps to ktime_get_ts().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index b4d6697..d854fb3 100644
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -932,7 +932,7 @@
 				   struct timespec *tv)
 {
 	if (runtime->tstamp_type == SNDRV_PCM_TSTAMP_TYPE_MONOTONIC)
-		do_posix_clock_monotonic_gettime(tv);
+		ktime_get_ts(tv);
 	else
 		getnstimeofday(tv);
 }