Input: drivers/usb/input - fix sparse warnings (signedness)

Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

drivers/usb/input/acecad.c

@@ -54,7 +54,7 @@ struct usb_acecad {
 	struct input_dev *input;
 	struct urb *irq;
 
-	signed char *data;
+	unsigned char *data;
 	dma_addr_t data_dma;
 };
 

drivers/usb/input/kbtab.c

@@ -29,7 +29,7 @@ module_param(kb_pressure_click, int, 0);
 MODULE_PARM_DESC(kb_pressure_click, "pressure threshold for clicks");
 
 struct kbtab {
-	signed char *data;
+	unsigned char *data;
 	dma_addr_t data_dma;
 	struct input_dev *dev;
 	struct usb_device *usbdev;

drivers/usb/input/wacom_wac.h

@@ -39,7 +39,7 @@ struct wacom_features {
 };
 
 struct wacom_wac {
-	signed char *data;
+	unsigned char *data;
         int tool[2];
         int id[2];
         __u32 serial[2];