x86/hpet: Remove unused parameter from hpet_next_event()

The clockevent device pointer is not used in this function.

While at it, rename the misnamed 'timer' parameter to 'channel', which makes it
clear what this parameter means.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Link: https://lkml.kernel.org/r/20190623132434.447880978@linutronix.de

arch/x86/kernel/hpet.c

@@ -347,15 +347,14 @@ static int hpet_resume(struct clock_event_device *evt)
 	return 0;
 }
 
-static int hpet_next_event(unsigned long delta,
-			   struct clock_event_device *evt, int timer)
+static int hpet_next_event(unsigned long delta, int channel)
 {
 	u32 cnt;
 	s32 res;
 
 	cnt = hpet_readl(HPET_COUNTER);
 	cnt += (u32) delta;
-	hpet_writel(cnt, HPET_Tn_CMP(timer));
+	hpet_writel(cnt, HPET_Tn_CMP(channel));
 
 	/*
 	 * HPETs are a complete disaster. The compare register is
@@ -407,7 +406,7 @@ static int hpet_legacy_resume(struct clock_event_device *evt)
 static int hpet_legacy_next_event(unsigned long delta,
 			struct clock_event_device *evt)
 {
-	return hpet_next_event(delta, evt, 0);
+	return hpet_next_event(delta, 0);
 }
 
 /*
@@ -508,7 +507,8 @@ static int hpet_msi_next_event(unsigned long delta,
 				struct clock_event_device *evt)
 {
 	struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt);
-	return hpet_next_event(delta, evt, hdev->num);
+
+	return hpet_next_event(delta, hdev->num);
 }
 
 static irqreturn_t hpet_interrupt_handler(int irq, void *data)