[media] gpio-ir-recv: a couple signedness bugs

There are couple places where we check unsigned values for negative.  I
changed ->gpin_nr to signed because in gpio_ir_recv_probe() we do:
        if (pdata->gpio_nr < 0)
                return -EINVAL;
I also change gval to a signed int in gpio_ir_recv_irq() because that's
the type that gpio_get_value_cansleep() returns and we test for negative
returns.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Trilok Soni <tsoni@codeaurora.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/rc/gpio-ir-recv.c

@@ -26,14 +26,14 @@
 
 struct gpio_rc_dev {
 	struct rc_dev *rcdev;
-	unsigned int gpio_nr;
+	int gpio_nr;
 	bool active_low;
 };
 
 static irqreturn_t gpio_ir_recv_irq(int irq, void *dev_id)
 {
 	struct gpio_rc_dev *gpio_dev = dev_id;
-	unsigned int gval;
+	int gval;
 	int rc = 0;
 	enum raw_event_type type = IR_SPACE;
 

include/media/gpio-ir-recv.h

@@ -14,7 +14,7 @@
 #define __GPIO_IR_RECV_H__
 
 struct gpio_ir_recv_platform_data {
-	unsigned int gpio_nr;
+	int gpio_nr;
 	bool active_low;
 };