Don't get iw version from git if there is no .git/

The version.sh script should only try to get the version from git if the
source actually resides in a git repository, i.e. .git/ exists. Doing
otherwise in a non-git source repo results in git ascending until it
finds a .git directory, which will cause problems in some source-based
distributions ( https://bugs.gentoo.org/show_bug.cgi?id=482334 ).
iw: add support for 5 and 10 MHz channels in IBSS mode

5/10 MHz requires to send the frequency information as chandef instead
of the the old channel type, therfore send the chandef next the channel
type (the latter is still used for old kernels).

Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
update nl80211.h
iw: Use NL80211_FREQUENCY_ATTR_NO_IR channel attribute

Align iw with the change in nl80211.h where NL80211_FREQUENCY_ATTR_NO_IBSS
and NL80211_FREQUENCY_ATTR_PASSIVE_SCAN were replaced by
NL80211_FREQUENCY_ATTR_NO_IR.

In case both NL80211_FREQUENCY_ATTR_NO_IR and __NL80211_FREQUENCY_ATTR_NO_IBSS
are set, assume that a new kernel is used and use the NO_IR notation,
otherwise use the previous notation.

This change requires nl80211.h with the new definitions

Signed-off-by: Ilan Peer <ilan.peer@intel.com>