Un-disable NL80211_FEATURE_SK_TX_STATUS in old kernels.

We've patched our kernels to make it available.

Change-Id: I0efd5d3cd5d70c9a71240e3705044c9e7722ed86
diff --git a/backport-include/linux/nl80211.h b/backport-include/linux/nl80211.h
index fcb0b8b..2521809 100644
--- a/backport-include/linux/nl80211.h
+++ b/backport-include/linux/nl80211.h
@@ -3,8 +3,6 @@
 #include_next <linux/nl80211.h>
 #include <linux/version.h>
 
-#if LINUX_VERSION_CODE < KERNEL_VERSION(3,3,0)
-#define NL80211_FEATURE_SK_TX_STATUS 0
-#endif
+#define NL80211_FEATURE_SK_TX_STATUS 1
 
 #endif /* __BACKPORT_LINUX_NL80211_H */