PR libstdc++/83566 - cyl_bessel_j returns wrong result for x>1000

PR libstdc++/83566 - cyl_bessel_j returns wrong result for x>1000

2018-11-16  Michele Pezzutti <mpezz@tiscali.it>
	    Edward Smith-Rowland  <3dw4rd@verizon.net>

	PR libstdc++/83566 - cyl_bessel_j returns wrong result for x>1000
	for high orders.
	* include/tr1/bessel_function.tcc: Perform no fewer than nu/2 iterations
	of the asymptotic series (nu is the Bessel order).
	* testsuite/tr1/5_numerical_facilities/special_functions/
	09_cyl_bessel_j/check_value.cc: Add tests at nu=100, 1000<=x<=2000.
	* testsuite/tr1/5_numerical_facilities/special_functions/
	11_cyl_neumann/check_value.cc: Ditto.
	* testsuite/special_functions/08_cyl_bessel_j/check_value.cc: Ditto.
	* testsuite/special_functions/10_cyl_neumann/check_value.cc: Ditto.

Co-Authored-By: Edward Smith-Rowland <3dw4rd@verizon.net>
From-SVN: r266252