Input: atmel_mxt_ts - fix lost interrupts

After commit 74d905d devices requiring the workaround for edge
triggered interrupts stopped working.

The hardware needs the quirk to be used before even proceeding to
check if the quirk is needed because mxt_acquire_irq() is called
before mxt_check_retrigen() is called and at this point pending IRQs
need to be checked, and if the workaround is not active, all
interrupts will be lost from this point.

Solve this by switching the calls around.

Reported-by: Andre Müller <andre.muller@web.de>
Tested-by: Andre Müller <andre.muller@web.de>
Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Fixes: 74d905d ("Input: atmel_mxt_ts - only read messages in mxt_acquire_irq() when necessary")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201201123026.1416743-1-linus.walleij@linaro.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/atmel_mxt_ts.c

@@ -2183,11 +2183,11 @@ static int mxt_initialize(struct mxt_data *data)
 		msleep(MXT_FW_RESET_TIME);
 	}
 
-	error = mxt_acquire_irq(data);
+	error = mxt_check_retrigen(data);
 	if (error)
 		return error;
 
-	error = mxt_check_retrigen(data);
+	error = mxt_acquire_irq(data);
 	if (error)
 		return error;