ck to normal operation state.

The internal hw scan will only perform passive scan on the first
available channel (not the channel being used) in associated state. The
request should be ignored if already performing scan operation or STA is
not in associated state.

Also include an "internal_scan" debugfs file to help trigger the
internal scan from user mode.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>