Fix typos in /Documentation : 'T''

This patch fixes typos in various Documentation txts. The patch addresses some
+words starting with the letter 'T'.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/Documentation/scsi/st.txt b/Documentation/scsi/st.txt
index 5ff65b1..3c12422 100644
--- a/Documentation/scsi/st.txt
+++ b/Documentation/scsi/st.txt
@@ -261,7 +261,7 @@
 used instead of the equal mark. The definition is prepended by the
 string st=. Here is an example:
 
-	st=buffer_kbs:64,write_threhold_kbs:60
+	st=buffer_kbs:64,write_threshold_kbs:60
 
 The following syntax used by the old kernel versions is also supported: