Fix misspellings of "system", "controller", "interrupt" and "necessary".

Fix the various misspellings of "system", controller", "interrupt" and
"[un]necessary".

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
diff --git a/fs/super.c b/fs/super.c
index d28fde7..ed1b93c 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -417,7 +417,7 @@
 }
 
 /*
- * Call the ->sync_fs super_op against all filesytems which are r/w and
+ * Call the ->sync_fs super_op against all filesystems which are r/w and
  * which implement it.
  *
  * This operation is careful to avoid the livelock which could easily happen
@@ -425,7 +425,7 @@
  * is used only here.  We set it against all filesystems and then clear it as
  * we sync them.  So redirtied filesystems are skipped.
  *
- * But if process A is currently running sync_filesytems and then process B
+ * But if process A is currently running sync_filesystems and then process B
  * calls sync_filesystems as well, process B will set all the s_need_sync_fs
  * flags again, which will cause process A to resync everything.  Fix that with
  * a local mutex.