arm64/arch_timer: Fix MMIO byteswap

The readl_relaxed() to __raw_readl() change meant to loose the
instrumentation, but also (inadvertently) lost the byteswap.

Fixes: 24ee7607 ("arm64/arch_timer: Provide noinstr sched_clock_read() functions")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20230606080614.GB905437@hirez.programming.kicks-ass.net

drivers/clocksource/arm_arch_timer.c

@@ -776,9 +776,9 @@ static noinstr u64 arch_counter_get_cnt_mem(struct arch_timer *t, int offset_lo)
 	u32 cnt_lo, cnt_hi, tmp_hi;
 
 	do {
-		cnt_hi = __raw_readl(t->base + offset_lo + 4);
-		cnt_lo = __raw_readl(t->base + offset_lo);
-		tmp_hi = __raw_readl(t->base + offset_lo + 4);
+		cnt_hi = __le32_to_cpu((__le32 __force)__raw_readl(t->base + offset_lo + 4));
+		cnt_lo = __le32_to_cpu((__le32 __force)__raw_readl(t->base + offset_lo));
+		tmp_hi = __le32_to_cpu((__le32 __force)__raw_readl(t->base + offset_lo + 4));
 	} while (cnt_hi != tmp_hi);
 
 	return ((u64) cnt_hi << 32) | cnt_lo;