wireless: rename ht_info to ht_operation

Since some of the HT code pre-dates 802.11n-2009
some names are wrong. The one that bothers me most
is that "HT operation" is called "HT information"
in our code and that causes confusion.

Rename "HT information" to "HT operation" and also
the control_chan field to primary_chan to match
the name used in the spec.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>