oprofile: reset bt_lost_no_mapping with other stats

The bt_lost_no_mapping is not getting reset at the start of a
profiling run, thus the oprofiled.log shows erroneous values for this
statistic. The attached patch fixes this problem.
Signed-off-by: Maynard Johnson <maynardj@us.ibm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

drivers/oprofile/oprofile_stats.c

@@ -33,6 +33,7 @@ void oprofile_reset_stats(void)
 	atomic_set(&oprofile_stats.sample_lost_no_mm, 0);
 	atomic_set(&oprofile_stats.sample_lost_no_mapping, 0);
 	atomic_set(&oprofile_stats.event_lost_overflow, 0);
+	atomic_set(&oprofile_stats.bt_lost_no_mapping, 0);
 }