iwlwifi/iwl3945: fix suspend resume association bug

iwlwifi/iwl3945: fix suspend resume association bug

Patch fixes the following bugs at
http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=2005
http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=2007

If we suspend with an association and then resumed,
we need to synchronize the active rxon with staging rxon,
else we will get an error when iwl_alive_start try to commit
rxon and staging is set to channel 0. Before going to suspend
staging and active rxon are in sync. After resuming from the
suspend, iwl_mac_start is called and it clears the staging
rxon. Patch fixes the bug by not clearing the staging rxon
in iwl_mac_start.

Patch also adds similar fix to 3945.

Signed-off-by: Abhijeet Kolekar <abhijeet.kolekar@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>