Input: apbps2 - remove useless variable

Fix the following gcc warning:

drivers/input/serio/apbps2.c:106:16: warning: variable ‘tmp’ set but not
used [-Wunused-but-set-variable].

Reported-by: Abaci Robot <[e-mail]>
Signed-off-by: Jiapeng Chong <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/serio/apbps2.c

···
 {
 	struct apbps2_priv *priv = io->port_data;
 	int limit;
-	unsigned long tmp;
 
 	/* clear error flags */
 	iowrite32be(0, &priv->regs->status);
···
 	/* Clear old data if available (unlikely) */
 	limit = 1024;
 	while ((ioread32be(&priv->regs->status) & APBPS2_STATUS_DR) && --limit)
-		tmp = ioread32be(&priv->regs->data);
+		ioread32be(&priv->regs->data);
 
 	/* Enable reciever and it's interrupt */
 	iowrite32be(APBPS2_CTRL_RE | APBPS2_CTRL_RI, &priv->regs->ctrl);