tools/times.sh: adapt comment to the actual loops

left over from #ea9f0718

Signed-off-by: Toralf Förster <toralf.foerster@gmx.de>

tools/times.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 #
-# Simple script to generate times.log that contains timing information for the last 20 revisions
+# Simple script to generate times.log that contains timing information for the last <n> revisions
 # Typically these commands shall be used to get times.txt:
 mkdir -p src
 cp lib/* src/   # fill src/ with some source code