Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index c532cb2..aeb739e 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -5,7 +5,7 @@
  * handling and other fixed offset specific things.
  *
  * This file is meant to be #included from head_64.S due to
- * position dependant assembly.
+ * position dependent assembly.
  *
  * Most of this originates from head_64.S and thus has the same
  * copyright history.