usb: gadget: rndis: use signed type for a signed value

rndis_get_nr() returns either a non-negative value on success
or a negative value on failure. In case of failure an error code
is returned to the caller of rndis_register().
If the "i" is unsigned, the information about error from rndis_get_nr()
is lost. If there is no error but rndis_get_nr() returns a value greater
than 256 the least significant bits of i are zero effectively limiting the
number of configs to 256.

This patch fixes that.

Signed-off-by: Andrzej Pietrasiewicz <[e-mail]>
Signed-off-by: Felipe Balbi <[e-mail]>

drivers/usb/gadget/function/rndis.c

···
 struct rndis_params *rndis_register(void (*resp_avail)(void *v), void *v)
 {
 	struct rndis_params *params;
-	u8 i;
+	int i;
 
 	if (!resp_avail)
 		return ERR_PTR(-EINVAL);
···
 
 void rndis_deregister(struct rndis_params *params)
 {
-	u8 i;
+	int i;
 
 	pr_debug("%s:\n", __func__);
 

drivers/usb/gadget/function/rndis.h

···
 
 typedef struct rndis_params
 {
-	u8			confignr;
+	int			confignr;
 	u8			used;
 	u16			saved_filter;
 	enum rndis_state	state;