iwl3945: fix compilation error in iwl3945_pass_packet_to_mac80211()

iwl3945: fix compilation error in iwl3945_pass_packet_to_mac80211()

Commit "iwlwifi: Traffic type and counter for debugFs" broke iwl3945 in
a case when CONFIG_IWLWIFI_LEDS is disabled:

drivers/net/wireless/iwlwifi/iwl-3945.c:580: error: 'hdr' undeclared (first use in this function)

Fix it by removing the ifdef check for hdr variable.

Signed-off-by: Kalle Valo <kalle.valo@iki.fi>
Acked-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>