Update some comments

Signed-off-by: Pengyu Lv <pengyu.lv@arm.com>

.travis.yml

@@ -52,7 +52,7 @@ jobs:
         - programs/test/selftest
         - tests/scripts/test_psa_constant_names.py
         - tests/ssl-opt.sh
-        # Modern OpenSSL does not support fixed ECDH or null ciphers.
+        # Modern OpenSSL does not support null ciphers.
         - tests/compat.sh -p OpenSSL -e 'NULL'
         - tests/scripts/travis-log-failure.sh
         # GnuTLS supports CAMELLIA but compat.sh doesn't properly enable it.

tests/compat.sh

@@ -614,7 +614,7 @@ setup_arguments()
     esac
 
     case $($OPENSSL ciphers ALL) in
-        *ECDH-ECDSA*) O_SUPPORT_ECDH="YES";;
+        *ECDH-ECDSA*|*ECDH-RSA*) O_SUPPORT_ECDH="YES";;
         *) O_SUPPORT_ECDH="NO";;
     esac
 
@@ -834,7 +834,7 @@ run_client() {
             if [ $EXIT -eq 0 ]; then
                 RESULT=0
             else
-                # If the cipher isn't supported...
+                # If it is NULL cipher ...
                 if grep 'Cipher is (NONE)' $CLI_OUT >/dev/null; then
                     RESULT=1
                 else