Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 2bef570..f0605ab 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -868,7 +868,7 @@
 }
 
 /*
- * Some rules/values in blkg have changed. Propogate those to respective
+ * Some rules/values in blkg have changed. Propagate those to respective
  * policies.
  */
 static void blkio_update_blkg_policy(struct blkio_cgroup *blkcg,
@@ -903,7 +903,7 @@
 }
 
 /*
- * A policy node rule has been updated. Propogate this update to all the
+ * A policy node rule has been updated. Propagate this update to all the
  * block groups which might be affected by this update.
  */
 static void blkio_update_policy_node_blkg(struct blkio_cgroup *blkcg,