new support for Raspberry Pi B+

[draymond at FoxValley.net]

>> There was a recent update to the Raspberry Pi wiki here:
>>
>> https://wiki.freebsd.org/FreeBSD/arm/Raspberry%20Pi
>>
>> ...
>
> That was the date when the fix was committed, it only means it will be
> included on the images created after that date.
>
> But yes, this is an oversight because i don't know how frequently the
> images are updated.
>
> Sorry but we have to wait.


Luiz, I was able to test your changes by overwriting the boot files on  
an existing image  
(FreeBSD-11.0-CURRENT-arm-armv6-RPI-B-20140918-r271779.img).  Your  
commit notes mention that you made some fixes regarding SD card  
compatibility.  However, I am still having problems with my SD cards.

I have a 16GB Transcend that gives me intermittent boot failures  
("Mounting from ufs:/dev/mmcsd0s2a failed with error 19").  I am able  
to suppress those failures as follows:

echo 'hw.bcm2835.sdhci.hs="0"' >> /boot/loader.conf

I also have a 32GB SanDisk that fails consistently during boot:

mmcsd0: Error indicated: 1 Timeout
g_vfs_done():mmcsd0s2a[READ(offset=852987904, length=4096)]error = 5
vnode_pager_getpages: I/O read error
vm_fault: pager read error, pid 1 (init)

I have not found a way to resolve this one.