iwlwifi: fix typo in comment

Change "anntena" to "antenna" in a comment in stats.h.

Signed-off-by: Mordechay Goodstein <mordechay.goodstein@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20201209231352.abca200b24d6.If5ce9e8abd5034496e98e97a53c446f045438388@changeid


Signed-off-by: Luca Coelho <luciano.coelho@intel.com>