core & avpops: fix overlapping avp flag

- k avpops uses a flag to mark whether a loaded avp from db has changed,
  in order to decide if worth to update db
- the value was overlapping with flags defined in sr core
- reported by Juha Heinanen

modules/avpops/avpops_impl.h

@@ -41,7 +41,7 @@
 
 /* flags used inside avps */
 /* IMPORTANT: flagss 0-4 are reserved by core; 8-15 by script */
-#define AVP_IS_IN_DB    (1<<7)
+#define AVP_IS_IN_DB    (1<<12)
 
 /* DB flags */
 #define AVPOPS_DB_NAME_INT   (1<<1)

usr_avp.h

@@ -153,7 +153,11 @@ typedef struct avp_spec {
 #define AVP_INDEX_BACKWARD	(1<<11)
 #define AVP_INDEX_ALL		(AVP_INDEX_FORWARD | AVP_INDEX_BACKWARD)
 
-#define AVP_CUSTOM_FLAGS	12
+/* AVP DB flag used by avpops module - defined in avpops
+ * - kept here for reference */
+// #define AVP_IS_IN_DB    (1<<12)
+
+#define AVP_CUSTOM_FLAGS	13
 
 #define GALIAS_CHAR_MARKER  '$'