btrfs: Fix misspellings in comments.

Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 80857b4..e2b54d5 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2749,7 +2749,7 @@
 	    em->start + em->len < chunk_offset) {
 		/*
 		 * This is a logic error, but we don't want to just rely on the
-		 * user having built with ASSERT enabled, so if ASSERT doens't
+		 * user having built with ASSERT enabled, so if ASSERT doesn't
 		 * do anything we still error out.
 		 */
 		ASSERT(0);
@@ -4119,7 +4119,7 @@
  * Callback for btrfs_uuid_tree_iterate().
  * returns:
  * 0	check succeeded, the entry is not outdated.
- * < 0	if an error occured.
+ * < 0	if an error occurred.
  * > 0	if the check failed, which means the caller shall remove the entry.
  */
 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,