fixed sentence upon Sujith's feedback

Author: Ottavio Campana

doc/Security.xml

@@ -2302,10 +2302,9 @@
             <para>If the key pair that the certificate shall be linked to does not have status
                 <emphasis>ok</emphasis>, an InvalidKeyStatus fault is produced, and the uploaded
               certificate is not stored in the keystore.</para>
-            <para>If the signature algorithm of the signature of the supplied certificate is based
-              on is not supported by the device, the device shall generate an
-              UnsupportedSignatureAlgorithm fault and shall not store the uploaded certificate nor
-              the contained public key in the keystore.</para>
+            <para>If the signature algorithm of the supplied certificate is not supported by the
+              device, the device shall generate an UnsupportedSignatureAlgorithm fault and shall not
+              store the uploaded certificate nor the contained public key in the keystore.</para>
             <para>If the device cannot process the uploaded certificate, a BadCertificate fault is
               produced and neither the uploaded certificate nor the public key are stored in the
               device’s keystore. The BadCertificate fault shall not be produced based on the mere