rsi: define RSI_USB_BUF_SIZE macro

RSI_USB_BUF_SIZE macro is used instead of hardcoding a buffer
size to 4096.
Signed-off-by: Amitkumar Karwar <amit.karwar@redpinesignals.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/rsi/rsi_91x_usb.c

@@ -293,12 +293,12 @@ int rsi_usb_write_register_multiple(struct rsi_hw *adapter,
 	u8 transfer;
 	int status = 0;
 
-	buf = kzalloc(4096, GFP_KERNEL);
+	buf = kzalloc(RSI_USB_BUF_SIZE, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
 
 	while (count) {
-		transfer = (u8)(min_t(u32, count, 4096));
+		transfer = (u8)(min_t(u32, count, RSI_USB_BUF_SIZE));
 		memcpy(buf, data, transfer);
 		status = usb_control_msg(dev->usbdev,
 					 usb_sndctrlpipe(dev->usbdev, 0),

drivers/net/wireless/rsi/rsi_usb.h

@@ -35,6 +35,8 @@
 #define MGMT_EP                      1
 #define DATA_EP                      2
 
+#define RSI_USB_BUF_SIZE	     4096
+
 struct rsi_91x_usbdev {
 	struct rsi_thread rx_thread;
 	u8 endpoint;