qcacmn: Define BAND_UNKNOWN in enum band_info

Define BAND_UNKNOWN in enum band_info

Change-Id: Icae4576b5c511fb8d74fd2bcef95642b416a56e4
CRs-Fixed: 2154595

umac/regulatory/dispatcher/inc/reg_services_public_struct.h

@@ -740,11 +740,13 @@ struct cur_regulatory_info {
  * @BAND_ALL:all bands
  * @BAND_2G: 2G band
  * @BAND_5G: 5G band
+ * @BAND_UNKNOWN: Unsupported band
  */
 enum band_info {
 	BAND_ALL,
 	BAND_2G,
 	BAND_5G,
+	BAND_UNKNOWN
 };
 
 /**