I spotted what looks to be a typo in if_iwm.c given the context in which it occurs. Patch attached. Apologies if I'm mistaken.
-- Bryan Index: if_iwm.c =================================================================== RCS file: /cvs/src/sys/dev/pci/if_iwm.c,v retrieving revision 1.211 diff -u -r1.211 if_iwm.c --- if_iwm.c 13 Aug 2017 18:08:03 -0000 1.211 +++ if_iwm.c 23 Aug 2017 12:43:19 -0000 @@ -5643,7 +5643,7 @@ err = iwm_power_update_device(sc); if (err) { - printf("%s: could send power command (error %d)\n", + printf("%s: could not send power command (error %d)\n", DEVNAME(sc), err); return err; } @@ -6313,7 +6313,7 @@ err = iwm_power_update_device(sc); if (err) { - printf("%s: could send power command (error %d)\n", + printf("%s: could not send power command (error %d)\n", DEVNAME(sc), err); goto err; }