USB NET KL5KUSB101: Fix mem leak in error path of kaweth_download_firmware()

We will leak the storage allocated by request_firmware() if the size of
the firmware is greater than KAWETH_FIRMWARE_BUF_SIZE.
This removes the leak by calling release_firmware() before we return
-ENOSPC.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/usb/kaweth.c b/drivers/net/usb/kaweth.c
index 5e98643..7dc8497 100644
--- a/drivers/net/usb/kaweth.c
+++ b/drivers/net/usb/kaweth.c
@@ -406,6 +406,7 @@
 
 	if (fw->size > KAWETH_FIRMWARE_BUF_SIZE) {
 		err("Firmware too big: %zu", fw->size);
+		release_firmware(fw);
 		return -ENOSPC;
 	}
 	data_len = fw->size;