trivial: fix then -> than typos in comments and documentation

- (better, more, bigger ...) then -> (...) than

Signed-off-by: Frederik Schwarzer <schwarzerf@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
index 0bef650..9832f9a 100644
--- a/fs/ubifs/gc.c
+++ b/fs/ubifs/gc.c
@@ -45,7 +45,7 @@
 #define SMALL_NODE_WM  UBIFS_MAX_DENT_NODE_SZ
 
 /*
- * GC may need to move more then one LEB to make progress. The below constants
+ * GC may need to move more than one LEB to make progress. The below constants
  * define "soft" and "hard" limits on the number of LEBs the garbage collector
  * may move.
  */