realtek: update SMP-related calls in prom_init()

realtek: update SMP-related calls in prom_init()

The availabibity of probing CPC depends on CONFIG_MIPS_CPC symbol and it
will be checked in arch/mips/include/asm/mips-cpc.h. RTL9310 selects
this symbol, so the family check is redudant.

Furthermore, mips_cm_probe() is already called from setup_arch() in
mips/kernel/setup.c before prom_init(), and as such is not required.

Also move mips_cpc_probe() to run just before registering SMP ops.

Signed-off-by: INAGAKI Hiroshi <musashino.open@gmail.com>
[squash SMP change commits, reword commit message]
Signed-off-by: Sander Vanheule <sander@svanheule.net>
---
This patch only really has an impact on the rtl931x subtarget, which has
no devices. Noboby is currently set up to test these patches either, but
the end result is closer to MIPS_GENERIC, so I do not expect it to cause
issues.