MFC r313317:

[iwm] Change 2nd arg of iwm_phy_db_set_section() to struct iwm_rx_packet.

* This matches the function declaration in Linux's iwlwifi.

MFC r313309:

[iwm] Sync if_iwm_phy_db code with Linux iwlwifi.

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

[iwm] Add and use iwm_phy_db_free(), to plug phy_db memory leak.

(Together with other iwm(4) memory leak fixes) Memory leakage in M_DEVBUF
is now at ca. 2KB for each iwm(4) module load/unload cycle.

Submitted by: Imre Vadasz <imre@vdsz.com>
Approved by: re (gjb)
Obtained from: DragonflyBSD git eaf551a1d464c643e98ce5781971dd32124e9af1
Differential Revision: https://reviews.freebsd.org/D6819

[iwm] Fix several nitpicks in iwm(4).

Move some declarations to if_iwmreg.h.
Remove iwm_fw_alive(); just call iwm_post_alive() directly.
Simplify iwm_mvm_add_sta().
Return timeout error from iwm_apm_init().
Print a message when init (i.e. boot) firmware fails to load.
Remove some commented-out code which wouldn't compile anyway.
Move iwm_mvm_tx_fifo to if_iwmreg.h to match better where Linux puts it.

Taken-From: OpenBSD (if_iwm.c r1.80 and if_iwmreg.h r1.11)

Submitted by: Imre Vadasz <imre@vdsz.com>
Obtained from: DragonflyBSD 29fcb331e5620ae145a6ab9cdda830e22fff626a

Import OpenBSD's iwm WiFi driver for Intel 3160/7260/7265.

There are still several bugs, but I've been using it for a while now.
Thanks to all the testers and to Adrian for his help with this
driver.

This driver isn't connected to the build yet, but it will be soon.

There's no MFC planned because the driver isn't very stable yet.

Reviewed by: adrian
Obtained from: https://github.com/rpaulo/iwm
Tested by: adrian, gjb, dumbbell (others that I forgot).
Relnotes: yes