Handle cases where a label terminates a construct before the end of a procedure (Fortran)

[zbeekman]

There is a problem returning the source location for the end of a procedure if a labeled construct (e.g. label do) immediately preceeds the end of the procedure. e.g.,

! ...
do 10, i = 1, 5
  ! Some loop body
  ! ...
10 continue
end subroutine foo