hpet: fix

Al Viro pointed out that there's a missing readl() of timer->hpet_config,
found by Sparse.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/hpet.c

@@ -137,9 +137,10 @@ static void hpet_reserve_platform_timers(unsigned long id)
 	hd.hd_irq[0] = HPET_LEGACY_8254;
 	hd.hd_irq[1] = HPET_LEGACY_RTC;
 
-	for (i = 2; i < nrtimers; timer++, i++)
-		hd.hd_irq[i] = (timer->hpet_config & Tn_INT_ROUTE_CNF_MASK) >>
+	for (i = 2; i < nrtimers; timer++, i++) {
+		hd.hd_irq[i] = (readl(&timer->hpet_config) & Tn_INT_ROUTE_CNF_MASK) >>
 			Tn_INT_ROUTE_CNF_SHIFT;
+	}
 
 	hpet_alloc(&hd);