prima: Fix sme command stuck

When iwpriv wlan0 reassoc is issued back to back, command from
smeCmdActiveList is not getting released and device goes into
a state after which connection and scan doesn't happen. Add proper
status when pConnectBssDesc is NULL to fix this.

Change-Id: I328b782cdf08e1504c0e53592e428d05d1b194a1