Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/include/linux/omap3isp.h b/include/linux/omap3isp.h
index 150822b..b6111f8 100644
--- a/include/linux/omap3isp.h
+++ b/include/linux/omap3isp.h
@@ -250,7 +250,7 @@
 /* Contains the information regarding the Horizontal Median Filter */
 struct omap3isp_h3a_af_hmf {
 	__u8 enable;	/* Status of Horizontal Median Filter */
-	__u8 threshold;	/* Threshhold Value for Horizontal Median Filter */
+	__u8 threshold;	/* Threshold Value for Horizontal Median Filter */
 };
 
 /* Contains the information regarding the IIR Filters */