Don't invoke dataConSrcToImplBang on newtypes
Trac #16141 was caused by StrictData
sneaking in some unwanted unpacking on the field of a newtype due to the dataConSrcToImplBang
function (which really only makes sense for data types) always being invoked from mkDataConRep
. Solution: don't invoke dataConSrcToImplBang
when dealing with newtypes.