riscv: cleanup riscv_cpuid_to_hartid_mask

Move the initial clearing of the mask from the callers to
riscv_cpuid_to_hartid_mask, and remove the unused !CONFIG_SMP stub.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>

arch/riscv/kernel/smp.c

@@ -56,6 +56,7 @@ void riscv_cpuid_to_hartid_mask(const struct cpumask *in, struct cpumask *out)
 {
 	int cpu;
 
+	cpumask_clear(out);
 	for_each_cpu(cpu, in)
 		cpumask_set_cpu(cpuid_to_hartid_map(cpu), out);
 }