[POWERPC] Fix mpc52xx serial driver to work for arch/ppc again

The mpc52xx_uart_of_enumerate() function was added when adding 52xx
support to arch/powerpc, but it must not be called for arch/ppc.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Paul Mackerras <paulus@samba.org>
1 file changed