libertas: Fix 'timer_list' stored private data related dot-rot

Fixes the following W=1 kernel build warning(s):

 drivers/net/wireless/marvell/libertas/main.c:727: warning: Function parameter or member 't' not described in 'lbs_cmd_timeout_handler'
 drivers/net/wireless/marvell/libertas/main.c:727: warning: Excess function parameter 'data' description in 'lbs_cmd_timeout_handler'
 drivers/net/wireless/marvell/libertas/main.c:761: warning: Function parameter or member 't' not described in 'lbs_tx_lockup_handler'
 drivers/net/wireless/marvell/libertas/main.c:761: warning: Excess function parameter 'data' description in 'lbs_tx_lockup_handler'
 drivers/net/wireless/marvell/libertas/main.c:784: warning: Function parameter or member 't' not described in 'auto_deepsleep_timer_fn'
 drivers/net/wireless/marvell/libertas/main.c:784: warning: Excess function parameter 'data' description in 'auto_deepsleep_timer_fn'

Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: libertas-dev@lists.infradead.org
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200819072402.3085022-15-lee.jones@linaro.org