auxdisplay: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Tested-by: Paul Burton <paul.burton@mips.com> # for img-ascii-lcd

drivers/auxdisplay/panel.c

@@ -1396,7 +1396,7 @@ static void panel_process_inputs(void)
 	}
 }
 
-static void panel_scan_timer(void)
+static void panel_scan_timer(struct timer_list *unused)
 {
 	if (keypad.enabled && keypad_initialized) {
 		if (spin_trylock_irq(&pprt_lock)) {
@@ -1421,7 +1421,7 @@ static void init_scan_timer(void)
 	if (scan_timer.function)
 		return;		/* already started */
 
-	setup_timer(&scan_timer, (void *)&panel_scan_timer, 0);
+	timer_setup(&scan_timer, panel_scan_timer, 0);
 	scan_timer.expires = jiffies + INPUT_POLL_TIME;
 	add_timer(&scan_timer);
 }