cpumask: Use accessors for cpu_*_mask: mips

Use the accessors rather than frobbing bits directly (the new versions
are const).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
diff --git a/arch/mips/kernel/smp-mt.c b/arch/mips/kernel/smp-mt.c
index 9538ca4..43e7cdc5 100644
--- a/arch/mips/kernel/smp-mt.c
+++ b/arch/mips/kernel/smp-mt.c
@@ -70,7 +70,7 @@
 		write_vpe_c0_vpeconf0(tmp);
 
 		/* Record this as available CPU */
-		cpu_set(tc, cpu_possible_map);
+		set_cpu_possible(tc, true);
 		__cpu_number_map[tc]	= ++ncpu;
 		__cpu_logical_map[ncpu]	= tc;
 	}