hyper: does not support disabling CURLOPT_HTTP_TRANSFER_DECODING

Simply because hyper doesn't have this ability. Mentioned in docs now.

Skip test 326 then

Closes #7889

docs/HYPER.md

@@ -49,6 +49,7 @@ over the wire with Hyper.
 The hyper backend doesn't support
 
 - `CURLOPT_IGNORE_CONTENT_LENGTH`
+- `--raw` and disabling `CURLOPT_HTTP_TRANSFER_DECODING`
 - RTSP
 
 ## Remaining issues

docs/libcurl/opts/CURLOPT_HTTP_TRANSFER_DECODING.3

@@ -49,7 +49,8 @@ if(curl) {
 }
 .fi
 .SH AVAILABILITY
-Added in 7.16.2
+Added in 7.16.2 Does not work with the hyper backend (it will always have
+transfer decoding enabled).
 .SH RETURN VALUE
 Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
 .SH "SEE ALSO"