lib/lru_cache: fix spelling mistake "colision"->"collision"

There is a spelling mistake in a literal string and in cariable names.
Fix these.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Deshan Zhang <[e-mail]>
Cc: Christoph Böhmwalder <[e-mail]>
Cc: Lars Ellenberg <[e-mail]>
Cc: Philipp Reisner <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

include/linux/lru_cache.h

···
 */
 
 /* this defines an element in a tracked set
- * .colision is for hash table lookup.
+ * .collision is for hash table lookup.
  * When we process a new IO request, we know its sector, thus can deduce the
  * region number (label) easily.  To do the label -> object lookup without a
  * full list walk, we use a simple hash table.
···
  * But it avoids high order page allocations in kmalloc.
  */
 struct lc_element {
-	struct hlist_node colision;
+	struct hlist_node collision;
 	struct list_head list;		 /* LRU list or free list */
 	unsigned refcnt;
 	/* back "pointer" into lc_cache->element[index],

lib/lru_cache.c

···
 
 	BUG_ON(!lc);
 	BUG_ON(!lc->nr_elements);
-	hlist_for_each_entry(e, lc_hash_slot(lc, enr), colision) {
+	hlist_for_each_entry(e, lc_hash_slot(lc, enr), collision) {
 		/* "about to be changed" elements, pending transaction commit,
 		 * are hashed by their "new number". "Normal" elements have
 		 * lc_number == lc_new_number. */
···
 	BUG_ON(e->refcnt);
 
 	e->lc_number = e->lc_new_number = LC_FREE;
-	hlist_del_init(&e->colision);
+	hlist_del_init(&e->collision);
 	list_move(&e->list, &lc->free);
 	RETURN();
 }
···
 	PARANOIA_LC_ELEMENT(lc, e);
 
 	e->lc_new_number = new_number;
-	if (!hlist_unhashed(&e->colision))
-		__hlist_del(&e->colision);
-	hlist_add_head(&e->colision, lc_hash_slot(lc, new_number));
+	if (!hlist_unhashed(&e->collision))
+		__hlist_del(&e->collision);
+	hlist_add_head(&e->collision, lc_hash_slot(lc, new_number));
 	list_move(&e->list, &lc->to_be_changed);
 
 	return e;