iostream.cc (istream::operator>>(long double&)): Scan value into separate variable, in case long double is bigger than double.

        * iostream.cc (istream::operator>>(long double&))
        [!_G_HAVE_LONG_DOUBLE_IO]: Scan value into separate variable, in
        case long double is bigger than double.
        (ostream::operator<<(double)) [_G_HAVE_PRINTF_FP]: Fix order of
        initializers of struct printf_info to match declaration order,
        to work around g++ bug.
        (ostream::operator<<(long double)) [_G_HAVE_PRINTF_FP]: Likewise.
        * gen-params: Add missing quotes.  Avoid useless use of command
        substitution.

From-SVN: r17582