[seL4] am335x - configs and refos

Attached are some patches for am335x support. I've started to play with refos, and can build it for am335x and run some of the startup (with release mode) but it hangs at some point.. still a work in progress. Also there's a few minor proofread tweaks on the refos doc. By the way, sel4test runs pretty well now in debug and release modes. Instructions are pretty straightforward: - build the project using the debug or release config - use objcopy to extract a raw binary from the ELF image - load the binary with uboot (I use "tftp", it defaults to the proper load address) - run it in uboot with "go 82000000" Tim