treewide: Fix typo in Documentation/DocBook

This patch fix spelling typo in Documentation/DocBook.
It is because .html and .xml files are generated by make htmldocs,
I have to fix a typo within the source files.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/input/sparse-keymap.c b/drivers/input/sparse-keymap.c
index a70aa55..e7409c4 100644
--- a/drivers/input/sparse-keymap.c
+++ b/drivers/input/sparse-keymap.c
@@ -236,7 +236,7 @@
  * in an input device that was set up by sparse_keymap_setup().
  * NOTE: It is safe to cal this function while input device is
  * still registered (however the drivers should care not to try to
- * use freed keymap and thus have to shut off interrups/polling
+ * use freed keymap and thus have to shut off interrupts/polling
  * before freeing the keymap).
  */
 void sparse_keymap_free(struct input_dev *dev)