x86: tsc_64.c make constant UL

arch/x86/kernel/tsc_64.c:245:13: warning: constant 0x100000000 is so big it is long

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/tsc_64.c b/arch/x86/kernel/tsc_64.c
index fcc16e5..c19b0e2 100644
--- a/arch/x86/kernel/tsc_64.c
+++ b/arch/x86/kernel/tsc_64.c
@@ -242,7 +242,7 @@
 	if (hpet) {
 		printk(KERN_INFO "TSC calibrated against HPET\n");
 		if (hpet2 < hpet1)
-			hpet2 += 0x100000000;
+			hpet2 += 0x100000000UL;
 		hpet2 -= hpet1;
 		tsc1 = (hpet2 * hpet_readl(HPET_PERIOD)) / 1000000;
 	} else {