naturally choose.  With only an effective -O0 gcc 4.0.1 doesn't produce
code as intented for copy_u8_altivec, causing liboil to fail at runtime.

Summary, liboil really needs -O2 (always).
Signed-off-by: David Flynn <davidf@rd.bbc.co.uk>
Signed-off-by: Felix Paul Kühne <fkuehne@videolan.org>