ixl(4)/ixlv(4): Update Intel XL710 PF and VF drivers to ixl-1.11.9 and ixlv-1.5.8

Update the legacy (non-iflib) drivers in stable/11 with recent changes from the
Intel out-of-tree version.

Major changes:

- Support for new BASE-T device with additional link speeds (2.5G and 5G) and EEE
- Additional I2C access methods backported from ixl-iflib
- FW LLDP Agent control with sysctl added for X722 devices (this already
existed for 710 devices)
- MAC/VLAN filters handling has been refactored
- Building and loading if_ixlv as a KLD has been fixed

This is not a MFC since the driver in 12/13 uses iflib, and the decision was
made to not use it in FreeBSD 11 releases.

Submitted by: Krzysztof Galazka <krzysztof.galazka@intel.com>
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D20290

MFC r333149: ixl(4): Update to 1.9.9-k

Major changes:

- Support for descriptor writeback mode (required by ixlv(4) for AVF support)
- Ability to disable firmware LLDP agent by user
- Fix for TX queue hang when using TSO
- Separate descriptor ring sizes for TX and RX rings

Approved by: re (marius)
Relnotes: yes
Sponsored by: Intel Corporation

MFC r313497: ixl(4): Update to 1.7.12-k.

Refresh upstream driver before impending conversion to iflib.

Major new features:

- Support for Fortville-based 25G adapters
- Support for I2C reads/writes

(To prevent getting or sending corrupt data, you should set
dev.ixl.0.debug.disable_fw_link_management=1 when using I2C
[this will disable link!], then set it to 0 when done. The driver implements
the SIOCGI2C ioctl, so ifconfig -v works for reading I2C data,
but there are read_i2c and write_i2c sysctls under the .debug sysctl tree
[the latter being useful for upper page support in QSFP+]).

- Addition of an iWARP client interface (so the future iWARP driver for
X722 devices can communicate with the base driver).
- Add "options IXL_IW" to kernel config to enable this option.

Sponsored by: Intel Corporation

MFC r303816 r303847
- Update ixl(4) to Intel driver version ixl-1.6.6-k
- Fixup RSS builds of ixl(4) missed during testing.

Approved by: re (gjb)