BOSTON — Smoke in the cabin has forced a US Airways flight from Spain to land in Boston, and an airline spokeswoman says four flight attendants have gone to the hospital to be evaluated. Spokeswoman Liz Landau says Flight 749 from Madrid was heading to Charlotte, N.C., Saturday morning with 192 passengers and a crew of nine, but had to land in Boston shortly after 11 a.m. Landau says the smoke had dissipated by the time the plane landed, and no passengers complained of any problems.