Booting problems after upgrade to FreeBSD 11

[Hedges Alexander]

Hi,

I recently upgrade from 10.3 to 11 from source and now I'm having some trouble booting.
I followed the steps outlined in "Rebuilding World" and there were no error messages
along the way. 

The problems are the following:
1) To use wireless networking I have to load the bwn_v4_ucode and the if_bwn kernel module.
I do this in loader.conf. The problem is that on the loader prompt I get the following error:
```
Loading /boot/defaults/loader.conf
/boot/kernel/kernel data=0xca3ac0+0x258cec syms=[0x4+0x8ce10+0x4+0xe9bb5]
/boot/entropy size=0x1000
/boot/kernel/if_bwn.ko text=0x3daf4 data=0x1a34+0x18 syms=[0x4+0x2460+0x4+0x28ca]
loading required module ‘kernel’
module ‘kernel’ exists but with wrong version
/boot/kernel/bwn_v4_ucode.ko text=0x1ec4 data=0x28a44 syms=[0x4+0x6b0+0x4+0xab8]
loading required module ‘kernel’
module ‘kernel’ exists but with wrong version
```
After booting of course the modules are not loaded, but strangely enough I can manually load
them with kldload and everything works fine.

2) may be linked to (1), but commenting out the entries in loader.conf does not solve
the problem. If I just let it boot, the device goes into a boot loop (constantly crashing
after the loader). For it to boot, I have to enter "?", "show" and then "auto-boot" or "boot-conf”.
I didn't test all combinations, but the above seems to be the safest bet to get it to boot.

Any ideas? Also, how can I debug the kernel crash? 

My machine is a PowerBook G4 from 2005.

Best Regards,
Alexander Hedges