nl80211: add Guard Interval support for set_bitrate_mask

Allow to force SGI, LGI.
Mainly for test purpose.

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index d10ba3a..d5e57bf 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1776,6 +1776,7 @@
 		u32 legacy;
 		u8 ht_mcs[IEEE80211_HT_MCS_MASK_LEN];
 		u16 vht_mcs[NL80211_VHT_NSS_MAX];
+		enum nl80211_txrate_gi gi;
 	} control[IEEE80211_NUM_BANDS];
 };
 /**