Beagleboard xM JTAG serial output issue

Hi,

Just dropping a note for those who don't follow U-Boot development. The
fix for the issue with serial output failing when a JTAG probe is
attached to the xM has made it to upstream U-Boot.

If you pull the latest mainline U-Boot you can now build an MLO and
u-boot.img that work properly.

See a3c3fabb0f65455068e01197e16927f0589beaa2 in
http://git.denx.de/u-boot.git/ for more info.

-Matt