proc/stat: remove arch_idle_time()

The last (only) architecture specific arch_idle_time() implementation was
removed with commit be76ea61 ("s390/idle: remove arch_cpu_idle_time()
and corresponding code").

Therefore remove the now dead code in fs/proc/stat.c as well.

Link: https://lkml.kernel.org/r/20230405143452.2677172-1-hca@linux.ibm.comSigned-off-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

fs/proc/stat.c

@@ -22,30 +22,6 @@
 #define arch_irq_stat() 0
 #endif
 
-#ifdef arch_idle_time
-
-u64 get_idle_time(struct kernel_cpustat *kcs, int cpu)
-{
-	u64 idle;
-
-	idle = kcs->cpustat[CPUTIME_IDLE];
-	if (cpu_online(cpu) && !nr_iowait_cpu(cpu))
-		idle += arch_idle_time(cpu);
-	return idle;
-}
-
-static u64 get_iowait_time(struct kernel_cpustat *kcs, int cpu)
-{
-	u64 iowait;
-
-	iowait = kcs->cpustat[CPUTIME_IOWAIT];
-	if (cpu_online(cpu) && nr_iowait_cpu(cpu))
-		iowait += arch_idle_time(cpu);
-	return iowait;
-}
-
-#else
-
 u64 get_idle_time(struct kernel_cpustat *kcs, int cpu)
 {
 	u64 idle, idle_usecs = -1ULL;
@@ -78,8 +54,6 @@ static u64 get_iowait_time(struct kernel_cpustat *kcs, int cpu)
 	return iowait;
 }
 
-#endif
-
 static void show_irq_gap(struct seq_file *p, unsigned int gap)
 {
 	static const char zeros[] = " 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0";