b43: stop leds during suspend

b43: stop leds during suspend

Call b43_leds_stop during suspend to avoid this WARN:

WARNING: CPU: 1 PID: 0 at net/mac80211/util.c:755 ieee80211_can_queue_work.isra.11+0x35/0x50 [mac80211]()
queueing ieee80211 work while going to suspend

 [...]

Call Trace:
 [<c165fb2a>] dump_stack+0x48/0x69
 [<c1052f7b>] warn_slowpath_common+0x8b/0xc0
 [<f9c30225>] ? ieee80211_can_queue_work.isra.11+0x35/0x50 [mac80211]
 [<f9c30225>] ? ieee80211_can_queue_work.isra.11+0x35/0x50 [mac80211]
 [<c1052fe3>] warn_slowpath_fmt+0x33/0x40
 [<f9c30225>] ieee80211_can_queue_work.isra.11+0x35/0x50 [mac80211]
 [<f9c30260>] ieee80211_queue_work+0x20/0x40 [mac80211]
 [<f9f25d78>] b43_led_brightness_set+0x28/0x30 [b43]
 [<c14f3835>] led_timer_function+0xd5/0xe0
 [<c10cb534>] call_timer_fn+0xa4/0x4a0

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>