[PATCH] clocksource/drivers/pistachio: Fix -Wunused-but-set-variable warning

[Drew Fustini]

Variable 'overflow' set but not used, but this is the intended behavior.
The hardware only updates the counter register after the overflow
register read. However, the value of overflow is not actually needed.

Link: https://lore.kernel.org/lkml/202111200402.afQsussU-lkp@xxxxxxxxx/
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Suggested-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Signed-off-by: Drew Fustini <dfustini@xxxxxxxxxxxx>
---
 drivers/clocksource/timer-pistachio.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/clocksource/timer-pistachio.c b/drivers/clocksource/timer-pistachio.c
index 6f37181a8c63..69c069e6f0a2 100644
--- a/drivers/clocksource/timer-pistachio.c
+++ b/drivers/clocksource/timer-pistachio.c
@@ -71,7 +71,8 @@ static u64 notrace
 pistachio_clocksource_read_cycles(struct clocksource *cs)
 {
 	struct pistachio_clocksource *pcs = to_pistachio_clocksource(cs);
-	u32 counter, overflow;
+	__maybe_unused u32 overflow;
+	u32 counter;
 	unsigned long flags;
 
 	/*
-- 
2.27.0