target/ppc: Split off common embedded TLB init Several 4xx CPUs and e200 share the same TLB settings enclosed in an ifdef. Split it off in a common function to reduce code duplication and the number of ifdefs. Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>