[MIPS] mips HPT cleanup: make clocksource_mips public

Make clocksource_mips public and get rid of mips_hpt_read,
mips_hpt_mask.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/sgi-ip27/ip27-timer.c b/arch/mips/sgi-ip27/ip27-timer.c
index e5441c3..7d36172 100644
--- a/arch/mips/sgi-ip27/ip27-timer.c
+++ b/arch/mips/sgi-ip27/ip27-timer.c
@@ -223,14 +223,14 @@
 	setup_irq(irqno, &rt_irqaction);
 }
 
-static unsigned int ip27_hpt_read(void)
+static cycle_t ip27_hpt_read(void)
 {
 	return REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT);
 }
 
 void __init ip27_time_init(void)
 {
-	mips_hpt_read = ip27_hpt_read;
+	clocksource_mips.read = ip27_hpt_read;
 	mips_hpt_frequency = CYCLES_PER_SEC;
 	xtime.tv_sec = get_m48t35_time();
 	xtime.tv_nsec = 0;