powerpc/book3e: Fix CPU feature handling on e5500 in 32-bit mode

We are missing FPU feature bit that user space may require.  In the
64-bit mode this gets set since we pull it in via COMMON_USER_PPC64.  We
just explicitly set it so user space will be happy again.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>