powerpc/setup: cleanup the #ifdef CONFIG_TAU block

Use cpu_has_feature() instead of opencoding

Use IS_ENABLED() instead of #ifdef for CONFIG_TAU_AVERAGE
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/setup-common.c

@@ -257,18 +257,18 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 	seq_printf(m, "\n");
 
 #ifdef CONFIG_TAU
-	if (cur_cpu_spec->cpu_features & CPU_FTR_TAU) {
-#ifdef CONFIG_TAU_AVERAGE
+	if (cpu_has_feature(CPU_FTR_TAU)) {
+		if (IS_ENABLED(CONFIG_TAU_AVERAGE)) {
 			/* more straightforward, but potentially misleading */
 			seq_printf(m,  "temperature \t: %u C (uncalibrated)\n",
 				   cpu_temp(cpu_id));
-#else
+		} else {
 			/* show the actual temp sensor range */
 			u32 temp;
 			temp = cpu_temp_both(cpu_id);
 			seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
 				   temp & 0xff, temp >> 16);
-#endif
+		}
 	}
 #endif /* CONFIG_TAU */