bridge/igb panic: sleepq_add: td 0xfffffe01bbce5300 to sleep on wchan 0xffffffff8157d9a0 with sleeping prohibited

Updating from latest CURRENT snapshot 
(FreeBSD-13.0-CURRENT-amd64-20200910-1544934ffb2) to r365620 broke the 
bridges with igb (I350-T2) for me.  Booting to kernel.old and/or 
commenting the entries in rc.conf helps.

rc.conf:
----
cloned_interfaces="bridge0 bridge1 tap0 tap1 tap2 tap3"
ifconfig_em0="inet ..."
ifconfig_igb0="up"
ifconfig_igb1="up"
ifconfig_bridge0="addm igb0 addm tap0 addm tap1"
ifconfig_bridge1="addm igb1 addm tap2 addm tap3"
----

NICs (em0 is on-board, igb0/igb1 is addon I350-T2 card):
----
em0: <Intel(R) PRO/1000 Network Connection> mem 0x92d00000-0x92d1ffff at 
device 31.6 numa-domain 0 on pci0
em0: Using 1024 TX descriptors and 1024 RX descriptors
em0: Using an MSI interrupt
em0: Ethernet address: e0:d5:5e:6c:aa:36
em0: netmap queues/slots: TX 1/1024, RX 1/1024
igb0: <Intel(R) PRO/1000 PCI-Express Network Driver> mem 
0xfbb00000-0xfbbfffff,0xfbc84000-0xfbc87fff at device 0.0 numa-domain 0 
on pci16
igb0: Using 1024 TX descriptors and 1024 RX descriptors
igb0: Using 8 RX queues 8 TX queues
igb0: Using MSI-X interrupts with 9 vectors
igb0: Ethernet address: a0:36:9f:0a:cf:42
igb0: netmap queues/slots: TX 8/1024, RX 8/1024
igb1: <Intel(R) PRO/1000 PCI-Express Network Driver> mem 
0xfba00000-0xfbafffff,0xfbc80000-0xfbc83fff at device 0.1 numa-domain 0 
on pci16
igb1: Using 1024 TX descriptors and 1024 RX descriptors
igb1: Using 8 RX queues 8 TX queues
igb1: Using MSI-X interrupts with 9 vectors
igb1: Ethernet address: a0:36:9f:0a:cf:43
igb1: netmap queues/slots: TX 8/1024, RX 8/1024
----

panic:
----
panic: sleepq_add: td 0xfffffe01bbce5300 to sleep on wchan 
0xffffffff8157d9a0 with sleeping prohibited
cpuid = 16
time = 1599808542
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 
0xfffffe01ba658c40
vpanic() at vpanic+0x182/frame 0xfffffe01ba658c90
panic() at panic+0x43/frame 0xfffffe01ba658cf0
sleepq_add() at sleepq_add+0x359/frame 0xfffffe01ba658d40
_sleep() at _sleep+0x20c/frame 0xfffffe01ba658df0
pause_sbt() at pause_sbt+0xfe/frame 0xfffffe01ba658e20
e1000_reset_hw_82580() at e1000_reset_hw_82580+0x1c8/frame 
0xfffffe01ba658e60
em_if_stop() at em_if_stop+0x1b/frame 0xfffffe01ba658e80
iflib_stop() at iflib_stop+0xbd/frame 0xfffffe01ba658ed0
iflib_if_ioctl() at iflib_if_ioctl+0x397/frame 0xfffffe01ba658f40
bridge_mutecaps() at bridge_mutecaps+0x145/frame 0xfffffe01ba658fb0
bridge_ioctl_add() at bridge_ioctl_add+0x468/frame 0xfffffe01ba659000
bridge_ioctl() at bridge_ioctl+0x32b/frame 0xfffffe01ba6590d0
in_control() at in_control+0x322/frame 0xfffffe01ba659180
ifioctl() at ifioctl+0x3e8/frame 0xfffffe01ba659250
kern_ioctl() at kern_ioctl+0x28e/frame 0xfffffe01ba6592c0
sys_ioctl() at sys_ioctl+0x127/frame 0xfffffe01ba659390
amd64_syscall() at amd64_syscall+0x140/frame 0xfffffe01ba6594b0
fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe01ba6594b0
--- syscall (54, FreeBSD ELF64, sys_ioctl), rip = 0x8004b4aba, rsp = 
0x7fffffffe2b8, rbp = 0x7fffffffe360 ---
Uptime: 14s
Dumping 3794 out of 97961 
MB:..1%..11%..21%..31%..41%..51%..61%..71%..81%..91%
----