ENOTSUPP is not a standard error code, don't use it. Replace with
EOPNOTSUPP instead.

No functional changes, compile tested only.
Signed-off-by: Karthikeyan Periyasamy <quic_periyasa@quicinc.com>
Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://msgid.link/20240117080431.2907471-2-quic_periyasa@quicinc.com