The collateral being for sale, just like the term of the loan, is a factor in determining whether you have a bridge or temporary loan, but not the only factor IMHO. To me, the repayment of the loan carries more weight. Generally a temporary or bridge loan is one that is intended to be replaced with permanent long-term financing.
In fact, the HMDA FAQ states that a spec home that is to be repaid with the funds from the sale of the property is a reportable purchase loan.
FAQ on Temporary Financing.