wifi: mt76: mt7925: fix incorrect TLV length in CLC command

wifi: mt76: mt7925: fix incorrect TLV length in CLC command

The previous implementation of __mt7925_mcu_set_clc() set the TLV length
field (.len) incorrectly during CLC command construction. The length was
initialized as sizeof(req) - 4, regardless of the actual segment length.
This could cause the WiFi firmware to misinterpret the command payload,
resulting in command execution errors.

This patch moves the TLV length assignment to after the segment is
selected, and sets .len to sizeof(req) + seg->len - 4, matching the
actual command content. This ensures the firmware receives the
correct TLV length and parses the command properly.

Fixes: c948b5da6bbe ("wifi: mt76: mt7925: add Mediatek Wi-Fi7 driver for mt7925 chips")
Cc: stable@vger.kernel.org
Signed-off-by: Quan Zhou <quan.zhou@mediatek.com>
Acked-by: Sean Wang <sean.wang@mediatek.com>
Link: https://patch.msgid.link/f56ae0e705774dfa8aab3b99e5bbdc92cd93523e.1772011204.git.quan.zhou@mediatek.com
Signed-off-by: Felix Fietkau <nbd@nbd.name>