tcp: rstreason: fully support in tcp_ack()

Based on the existing skb drop reason, updating the rstreason map can
help us finish the rstreason job in this function.

Signed-off-by: Jason Xing <kernelxing@tencent.com>
Link: https://lore.kernel.org/r/20240510122502.27850-3-kerneljasonxing@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>