Fix spelling and typographical errors found by cspell
Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
diff --git a/include/mbedtls/platform_util.h b/include/mbedtls/platform_util.h
index 5d2fefc..ecd36da 100644
--- a/include/mbedtls/platform_util.h
+++ b/include/mbedtls/platform_util.h
@@ -122,7 +122,7 @@
*
* This macro has an empty expansion. It exists for documentation purposes:
* a #MBEDTLS_CHECK_RETURN_OPTIONAL annotation indicates that the function
- * has been analyzed for return-check usefuless, whereas the lack of
+ * has been analyzed for return-check usefulness, whereas the lack of
* an annotation indicates that the function has not been analyzed and its
* return-check usefulness is unknown.
*/