iwlwifi: kill struct iwl4965_lq_mngr

This patch removes struct iwl4965_lq_mngr it is not used.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>