relayd.conf.5: clarify edh syntax to match parser behavior

The previous wording implied that omitting "params" defaulted to auto.
"edh" alone enables EDH in auto mode, while leaving the directive out
keeps EDH disabled (equivalent to no edh / edh params none).

OK?

diff --git a/relayd.conf.5 b/relayd.conf.5
index 6e95e9a..eb530ea 100644
--- a/relayd.conf.5
+++ b/relayd.conf.5
@@ -1003,12 +1003,15 @@ In
 .Ic legacy
 mode, a 1024 bit ephemeral key is used.
 If
-.Ic params
-is omitted,
-.Ic auto
+.Ic edh
+is given without
+.Ic params ,
+.Dq auto
 is used.
 The default is
-.Ic no edh .
+.Ic no edh 
+and is equivalent to
+.Ic edh params none .
 .It Ic keypair Ar name
 .It Ic keypair Ar name Op Ic cert Ar "path"
 .It Ic keypair Ar name Op Ic key Ar "path"