Fix typos in doc and comments

Changes persistant -> persistent. www.dictionary.com does not know
persistant (with an A), but should it be one of those things you can
spell in more than one correct way, let me know.

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/include/linux/textsearch.h b/include/linux/textsearch.h
index 7dac8f0..004808a 100644
--- a/include/linux/textsearch.h
+++ b/include/linux/textsearch.h
@@ -20,7 +20,7 @@
 /**
  * struct ts_state - search state
  * @offset: offset for next match
- * @cb: control buffer, for persistant variables of get_next_block()
+ * @cb: control buffer, for persistent variables of get_next_block()
  */
 struct ts_state
 {
@@ -71,7 +71,7 @@
 	 * Called repeatedly until 0 is returned. Must assign the
 	 * head of the next block of data to &*dst and return the length
 	 * of the block or 0 if at the end. consumed == 0 indicates
-	 * a new search. May store/read persistant values in state->cb.
+	 * a new search. May store/read persistent values in state->cb.
 	 */
 	unsigned int		(*get_next_block)(unsigned int consumed,
 						  const u8 **dst,