docs: Fix some broken references

As we move stuff around, some doc references are broken. Fix some of
them via this script:
	./scripts/documentation-file-ref-check --fix

Manually checked if the produced result is valid, removing a few
false-positives.

Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/Documentation/trace/histogram.txt b/Documentation/trace/histogram.txt
index b13771c..e73bcf9 100644
--- a/Documentation/trace/histogram.txt
+++ b/Documentation/trace/histogram.txt
@@ -7,7 +7,7 @@
 
   Histogram triggers are special event triggers that can be used to
   aggregate trace event data into histograms.  For information on
-  trace events and event triggers, see Documentation/trace/events.txt.
+  trace events and event triggers, see Documentation/trace/events.rst.
 
 
 2. Histogram Trigger Command