PPC 85xx QEMU: Always assume 1 core

We only need u-boot to bother about a single core in the QEMU machine.
Everything that would require additional knowledge of more cores gets
handled by QEMU and passed straight into the payload we execute.

Because of this setup, it would be counterproductive to enable SMP support
in u-boot. We would have to rip CPUs out of already existing spin tables
and respin them from u-boot. It would be a pretty big mess.

So only assume we have a single core. This fixes errors about CONFIG_MP
being disabled.

Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/powerpc/cpu/mpc8xxx/cpu.c b/arch/powerpc/cpu/mpc8xxx/cpu.c
index dfedc53..13bd0ac 100644
--- a/arch/powerpc/cpu/mpc8xxx/cpu.c
+++ b/arch/powerpc/cpu/mpc8xxx/cpu.c
@@ -177,7 +177,7 @@
 /*
  * Return a 32-bit mask indicating which cores are present on this SOC.
  */
-u32 cpu_mask(void)
+__weak u32 cpu_mask(void)
 {
 	ccsr_pic_t __iomem *pic = (void *)CONFIG_SYS_MPC8xxx_PIC_ADDR;
 	struct cpu_type *cpu = gd->arch.cpu;
@@ -196,7 +196,7 @@
 /*
  * Return the number of cores on this SOC.
  */
-int cpu_numcores(void)
+__weak int cpu_numcores(void)
 {
 	struct cpu_type *cpu = gd->arch.cpu;