dccp: Fill in the Data fields for "Option Error" Resets

This updates the use of the `out_invalid_option' label, which produces a 
Reset (code 5, "Option Error"), to fill in the  Data1...Data3 fields as
specified in RFC 4340, 5.6.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>