mac80211: document only injected *_RADIOTAP_* flags

Not the internal flags but the radiotap flags are parsed when the monitor
injected frames are prepared for transmission. Thus the documentation
should only document these.

Reported-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Fixes: dfdfc2beb0 ("mac80211: Parse legacy and HT rate in injected frames")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Documentation/networking/mac80211-injection.txt

@@ -37,8 +37,8 @@ radiotap headers and used to control injection:
    HT rate for the transmission (only for devices without own rate control).
    Also some flags are parsed
 
-   IEEE80211_TX_RC_SHORT_GI: use short guard interval
-   IEEE80211_TX_RC_40_MHZ_WIDTH: send in HT40 mode
+   IEEE80211_RADIOTAP_MCS_SGI: use short guard interval
+   IEEE80211_RADIOTAP_MCS_BW_40: send in HT40 mode
 
  * IEEE80211_RADIOTAP_DATA_RETRIES