Add 't0-56' testbed_type for fib_test.

[iris00522]

Description of PR

It's the same issue with losing t0-56 testbed_type.
I base on #954 bug fix to test bgp_speaker and I get the a fail messages when we run the test item of bgp_speaker.

"FAIL: fib_test.FibTest",
    "----------------------------------------------------------------------",
    "Traceback (most recent call last):",
    "  File \"ptftests/fib_test.py\", line 290, in runTest",
    "    self.check_ip_range()",
    "  File \"ptftests/fib_test.py\", line 138, in check_ip_range",
    "    self.check_ip_route(src_port, ip_range.get_last_ip(), exp_port_list, ipv4)",
    "  File \"ptftests/fib_test.py\", line 155, in check_ip_route",
    "    (matched_index, received) = self.check_ipv4_route(src_port, dst_ip_addr, dst_port_list)",
    "  File \"ptftests/fib_test.py\", line 200, in check_ipv4_route",
    "    return verify_packet_any_port(self, masked_exp_pkt, dst_port_list)",
    "  File \"/usr/lib/python2.7/dist-packages/ptf/testutils.py\", line 2373, in verify_packet_any_port",
    "    % (ports, device_number, result.format()))",
    "AssertionError: Did not receive expected packet on any of ports [2, 3, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 18, 19, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31] for device 0.",

I move the judgement of t0-64-32 to the self.src_ports = range(1, 25) + range(28, 32), and the test is success.

Summary:
Fixes #966

Type of change

• [] Bug fix
• [] Testbed and Framework(new/improvement)
• [v] Test case(new/improvement)

Approach

How did you do it?

How did you verify/test it?

add t0-56 testbed_type.

Any platform specific information?

Tested on the broadcom platform.

Documentation