Clarify wording of documentation

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/include/mbedtls/x509_crt.h b/include/mbedtls/x509_crt.h
index c6e20cf..4435f02 100644
--- a/include/mbedtls/x509_crt.h
+++ b/include/mbedtls/x509_crt.h
@@ -160,7 +160,7 @@
 {
     uint32_t allowed_mds;       /**< MDs for signatures         */
     uint32_t allowed_pks;       /**< PK algs for public keys;
-                                 *   this applies to any CRT
+                                 *   this applies to all certificates
                                  *   in the provided chain.     */
     uint32_t allowed_curves;    /**< Elliptic curves for ECDSA  */
     uint32_t rsa_min_bitlen;    /**< Minimum size for RSA keys  */