Only use standard cipher name

Signed-off-by: Pengyu Lv <pengyu.lv@arm.com>
diff --git a/tests/compat.sh b/tests/compat.sh
index 6c58a1b..ae7c682 100755
--- a/tests/compat.sh
+++ b/tests/compat.sh
@@ -1047,7 +1047,7 @@
                         start_server "OpenSSL"
                         translate_ciphers m $M_CIPHERS
                         for i in $ciphers; do
-                            o_check_ciphersuite "$i"
+                            o_check_ciphersuite "${i%%=*}"
                             run_client mbedTLS ${i%%=*} ${i#*=}
                         done
                         stop_server