iwlwifi: mvm: toggle tx antenna if tx fails during connection establishment

If tx fails during connection establishment, try another antenna for
the next tx. This will increase the chance to establish connection if
one of the antennas is blocked.  Note that the antenna is toggled even
when failing to tx data frames since connection establishment may use
EAPOLs for 802.1X authentication/ 4 way handshake.

Signed-off-by: Avraham Stern <avraham.stern@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>