powerpc: Drop redundant machine type print in show_cpuinfo

For many of the embedded boards, "model" and "Machine" are printing
the same thing; remove the redundant code and allow the generic
show_cpuinfo to print the model information.

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Acked-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Martyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>