Add support for iwm 3168 cards

[eadler]

Test Plan

Compiles, loads, and can produce a working wlan0 device.

iwm0@pci0:5:0:0:        class=0x028000 card=0x21108086 chip=0x24fb8086 rev=0x10 hdr=0x00
    vendor     = 'Intel Corporation'
    device     = 'Dual Band Wireless-AC 3168NGW [Stone Peak]'
    class      = network
[94829] iwm0: <Intel(R) Dual Band Wireless AC 3168> mem 0xef700000-0xef701fff at device 0.0 on pci5
[94829] iwm0: hw rev 0x220, fw ver 22.361476.0, address 28:c6:3f:15:43:c5

Here is where I need help:

iwm0: could not initiate scan

Reference https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=224886

[kevans]

sys/dev/iwm/if_iwm.c

5687

Nit: tab, rather than space, after #define

[ivadasz]

sys/conf/files

1991–1995

You should add .c and .fwo rules as well for the iwm3168 firmware blob.

[eadler]

per @kevans and @ivadasz

[eadler]

Closed in r331665