Bluetooth: mgmt: remove redundant assignment to variable cur_len

Variable cur_len is being ininitialized with a value in the start of
a for-loop but this is never read, it is being re-assigned a new value
on the first statement in the for-loop.  The initialization is redundant
and can be removed.

Cleans up clang scan build warning:
net/bluetooth/mgmt.c:7958:14: warning: Although the value stored to 'cur_len'
is used in the enclosing expression, the value is never actually read
from 'cur_len' [deadcode.DeadStores]
Signed-off-by: NColin Ian King <colin.i.king@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

net/bluetooth/mgmt.c

@@ -7955,7 +7955,7 @@ static bool tlv_data_is_valid(struct hci_dev *hdev, u32 adv_flags, u8 *data,
 		return false;
 
 	/* Make sure that the data is correctly formatted. */
-	for (i = 0, cur_len = 0; i < len; i += (cur_len + 1)) {
+	for (i = 0; i < len; i += (cur_len + 1)) {
 		cur_len = data[i];
 
 		if (!cur_len)