iwmc3200wifi: invalidate profile when necessary before connect

If cfg80211 requests to connect when we have already had an active
profile, invalidate the current profile first before sending a new
profile to UMAC.

Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>