mac80211: reorder channel and freq reporting in wext scan report

This patch switch order of channel and freq (SIOCGIWFREQ) reports
in scan results in order to overcome wpa_supplicant inability
to handle channel numbers in 5.2Ghz band.
Wext reporting channel number is ambiguous as channels 7-12 (802.11j)
exist on both bands.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>