mac80211: clean up an ieee80211_do_open error path
mac80211: clean up an ieee80211_do_open error path

Eliad's comment prompted me to look closer at
the error paths in ieee80211_do_open() and I
found one that should use the error labels.

Also add a comment about the clear_bit since
in many error cases the bit hasn't been set.

Cc: Eliad Peller <fdf5551f20996bc0613832b4b54eb06eecaffd38@wizery.com>
Signed-off-by: Johannes Berg <bff32994ff0f8d048f262a8388145a71b6071bfe@intel.com>
Signed-off-by: John W. Linville <2a53bac7a5d324865ef46ec4c38b2c0fba1456b4@tuxdriver.com>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs