[GITGRUB] Support new object format for powerpc-ieee1275

[Bean]

Hi,

Support new object format for powerpc-ieee1275 platform, I create the
image with cross compile in i386 environment, so that the elf
converter should be endianness safe.

There are still some problem, but they don't seems to be related to
the new object format, as it also exist in svn code. Claim memory
seems to fail, so the image halts pretty soon, tested with OpenBios
with qemu-ppc and ppc mac mini. And the calls to "output-device
output" in ofconsole would generate an exception, just comment it out
for now.

-- 
Bean

gitgrub home: http://github.com/grub/grub/
my fork page: http://github.com/bean123/grub/