net: usb: remove unused structs 'usb_context'

Both lan78xx and smsc75xx have a 'usb_context'
struct which is unused, since their original commits.

Remove them.
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Link: https://lore.kernel.org/r/20240526205922.176578-1-linux@treblig.orgSigned-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/usb/lan78xx.c

@@ -380,11 +380,6 @@ struct skb_data {		/* skb->cb is one of these */
 	int num_of_packet;
 };
 
-struct usb_context {
-	struct usb_ctrlrequest req;
-	struct lan78xx_net *dev;
-};
-
 #define EVENT_TX_HALT			0
 #define EVENT_RX_HALT			1
 #define EVENT_RX_MEMORY			2

drivers/net/usb/smsc75xx.c

@@ -61,11 +61,6 @@ struct smsc75xx_priv {
 	u8 suspend_flags;
 };
 
-struct usb_context {
-	struct usb_ctrlrequest req;
-	struct usbnet *dev;
-};
-
 static bool turbo_mode = true;
 module_param(turbo_mode, bool, 0644);
 MODULE_PARM_DESC(turbo_mode, "Enable multiple frames per Rx transaction");