Fix the following coccicheck warnings:

./drivers/hid/wacom_wac.c:2536:2-6: WARNING: Assignment of
0/1 to bool variable.

Reported-by: Abaci Robot <redacted>
Signed-off-by: Jiapeng Zhong <redacted>
---
 drivers/hid/wacom_wac.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
index 1bd0eb7..62b0f71 100644
--- a/drivers/hid/wacom_wac.c
+++ b/drivers/hid/wacom_wac.c

@@ -2533,7 +2533,7 @@ static void wacom_wac_finger_slot(struct wacom_wac *wacom_wac,
 	    !wacom_wac->shared->is_touch_on) {
 		if (!wacom_wac->shared->touch_down)
 			return;
-		prox = 0;
+		prox = false;
 	}