bpf: Remove the obsolte u64_stats_fetch_*_irq() users.

Now that the 32bit UP oddity is gone and 32bit uses always a sequence
count, there is no need for the fetch_irq() variants anymore.

Convert to the regular interface.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/bpf/20221026123110.331690-1-bigeasy@linutronix.de

kernel/bpf/syscall.c

@@ -2118,11 +2118,11 @@ static void bpf_prog_get_stats(const struct bpf_prog *prog,
 
 		st = per_cpu_ptr(prog->stats, cpu);
 		do {
-			start = u64_stats_fetch_begin_irq(&st->syncp);
+			start = u64_stats_fetch_begin(&st->syncp);
 			tnsecs = u64_stats_read(&st->nsecs);
 			tcnt = u64_stats_read(&st->cnt);
 			tmisses = u64_stats_read(&st->misses);
-		} while (u64_stats_fetch_retry_irq(&st->syncp, start));
+		} while (u64_stats_fetch_retry(&st->syncp, start));
 		nsecs += tnsecs;
 		cnt += tcnt;
 		misses += tmisses;