powerpc/ps3: Add missing check for PS3 to rtc-ps3 platform device registration
powerpc/ps3: Add missing check for PS3 to rtc-ps3 platform device registration

On non-PS3, we get:

| kernel BUG at drivers/rtc/rtc-ps3.c:36!

because the rtc-ps3 platform device is registered unconditionally in a kernel
with builtin support for PS3.

Reported-by: Sachin Sant <3cb3463e59fd47adefd284694e4e7b71899dd60f@in.ibm.com>
Signed-off-by: Geert Uytterhoeven <205f5bcb2ea42515c4425a82ddba45c7ca0f2905@sonycom.com>
Acked-by: Geoff Levand <058b6ffe73540731b6df5cbcf27480d0bdbf7afb@am.sony.com>
Signed-off-by: Benjamin Herrenschmidt <a7089bb6e7e92505d88aaff006cbdd60cc9120b6@kernel.crashing.org>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas