cfg80211: move IE split utilities here from mac80211

As the next patch will require the IE splitting utility functions
in cfg80211, move them there from mac80211.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/wireless/util.c b/net/wireless/util.c
index f218b15..70051ab 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -1290,6 +1290,47 @@
 }
 EXPORT_SYMBOL(cfg80211_get_p2p_attr);
 
+static bool ieee80211_id_in_list(const u8 *ids, int n_ids, u8 id)
+{
+	int i;
+
+	for (i = 0; i < n_ids; i++)
+		if (ids[i] == id)
+			return true;
+	return false;
+}
+
+size_t ieee80211_ie_split_ric(const u8 *ies, size_t ielen,
+			      const u8 *ids, int n_ids,
+			      const u8 *after_ric, int n_after_ric,
+			      size_t offset)
+{
+	size_t pos = offset;
+
+	while (pos < ielen && ieee80211_id_in_list(ids, n_ids, ies[pos])) {
+		if (ies[pos] == WLAN_EID_RIC_DATA && n_after_ric) {
+			pos += 2 + ies[pos + 1];
+
+			while (pos < ielen &&
+			       !ieee80211_id_in_list(after_ric, n_after_ric,
+						     ies[pos]))
+				pos += 2 + ies[pos + 1];
+		} else {
+			pos += 2 + ies[pos + 1];
+		}
+	}
+
+	return pos;
+}
+EXPORT_SYMBOL(ieee80211_ie_split_ric);
+
+size_t ieee80211_ie_split(const u8 *ies, size_t ielen,
+			  const u8 *ids, int n_ids, size_t offset)
+{
+	return ieee80211_ie_split_ric(ies, ielen, ids, n_ids, NULL, 0, offset);
+}
+EXPORT_SYMBOL(ieee80211_ie_split);
+
 bool ieee80211_operating_class_to_band(u8 operating_class,
 				       enum ieee80211_band *band)
 {