Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c
index 49c6513..9af0847 100644
--- a/arch/arm/mach-omap2/powerdomain.c
+++ b/arch/arm/mach-omap2/powerdomain.c
@@ -196,7 +196,7 @@
 /**
  * pwrdm_init - set up the powerdomain layer
  * @pwrdm_list: array of struct powerdomain pointers to register
- * @custom_funcs: func pointers for arch specfic implementations
+ * @custom_funcs: func pointers for arch specific implementations
  *
  * Loop through the array of powerdomains @pwrdm_list, registering all
  * that are available on the current CPU. If pwrdm_list is supplied