wlan: Fix overwrite of regulatory flags

In current implementation, REGULATORY_DISABLE_BEACON_HINTS is set but
overwritten with the REGULATORY_COUNTRY_IE_IGNORE, beacuse of which
passive scan flags and beaconing flags are lifted by cfg80211 due to
regulatory beacon hints.

This fix this, set both flags and avoid overwrite.

Change-Id: I8bc4f0c0275b9035414bdcdafa692bf1102a77cf
CRs-Fixed: 1054854
diff --git a/CORE/HDD/src/wlan_hdd_cfg80211.c b/CORE/HDD/src/wlan_hdd_cfg80211.c
index da718ce..895fb56 100644
--- a/CORE/HDD/src/wlan_hdd_cfg80211.c
+++ b/CORE/HDD/src/wlan_hdd_cfg80211.c
@@ -7919,7 +7919,7 @@
                  |  WIPHY_FLAG_HAS_REMAIN_ON_CHANNEL
                     | WIPHY_FLAG_OFFCHAN_TX;
 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,14,0))
-    wiphy->regulatory_flags = REGULATORY_COUNTRY_IE_IGNORE;
+    wiphy->regulatory_flags |= REGULATORY_COUNTRY_IE_IGNORE;
 #else
      wiphy->country_ie_pref = NL80211_COUNTRY_IE_IGNORE_CORE;
 #endif