Redo of PR#5345. Fixed spelling and typographical errors found by CodeSpell.

Signed-off-by: Shaun Case <warmsocks@gmail.com>
Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index c674506..e6e6ef4 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -3151,7 +3151,7 @@
                 MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER );
             return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
         }
-    } /* FALLTROUGH */
+    } /* FALLTHROUGH */
 #endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
 
 #if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) ||                       \