brcmfmac: set state of hanger slot to FREE when flushing PSQ

When USB or SDIO device got abnormal bus disconnection, host driver
tried to clean up the skbs in PSQ and TXQ (The skb's pointer in hanger
slot linked to PSQ and TSQ), so we should set the state of skb hanger slot
to BRCMF_FWS_HANGER_ITEM_STATE_FREE before freeing skb.
In brcmf_fws_bus_txq_cleanup it already sets
BRCMF_FWS_HANGER_ITEM_STATE_FREE before freeing skb, therefore we add the
same thing in brcmf_fws_psq_flush to avoid following warning message.

   [ 1580.012880] ------------   [ cut here ]------------
   [ 1580.017550] WARNING: CPU: 3 PID: 3065 at
drivers/net/wireless/broadcom/brcm80211/brcmutil/utils.c:49
brcmu_pkt_buf_free_skb+0x21/0x30 [brcmutil]
   [ 1580.184017] Call Trace:
   [ 1580.186514]  brcmf_fws_cleanup+0x14e/0x190 [brcmfmac]
   [ 1580.191594]  brcmf_fws_del_interface+0x70/0x90 [brcmfmac]
   [ 1580.197029]  brcmf_proto_bcdc_del_if+0xe/0x10 [brcmfmac]
   [ 1580.202418]  brcmf_remove_interface+0x69/0x190 [brcmfmac]
   [ 1580.207888]  brcmf_detach+0x90/0xe0 [brcmfmac]
   [ 1580.212385]  brcmf_usb_disconnect+0x76/0xb0 [brcmfmac]
   [ 1580.217557]  usb_unbind_interface+0x72/0x260
   [ 1580.221857]  device_release_driver_internal+0x141/0x200
   [ 1580.227152]  device_release_driver+0x12/0x20
   [ 1580.231460]  bus_remove_device+0xfd/0x170
   [ 1580.235504]  device_del+0x1d9/0x300
   [ 1580.239041]  usb_disable_device+0x9e/0x270
   [ 1580.243160]  usb_disconnect+0x94/0x270
   [ 1580.246980]  hub_event+0x76d/0x13b0
   [ 1580.250499]  process_one_work+0x144/0x360
   [ 1580.254564]  worker_thread+0x4d/0x3c0
   [ 1580.258247]  kthread+0x109/0x140
   [ 1580.261515]  ? rescuer_thread+0x340/0x340
   [ 1580.265543]  ? kthread_park+0x60/0x60
   [ 1580.269237]  ? SyS_exit_group+0x14/0x20
   [ 1580.273118]  ret_from_fork+0x25/0x30
   [ 1580.300446] ------------   [ cut here ]------------

Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Wright Feng <wright.feng@cypress.com>
Signed-off-by: Chi-hsien Lin <chi-hsien.lin@cypress.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200624091608.25154-2-wright.feng@cypress.com