pimd: When specifying 224.0.0.0/4 as the RP group inform msdp

When we modify the 224.0.0.0/4 rp address with a:
'ip pim rp A.B.C.D'

We need to let msdp know that this command was entered.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Reviewed-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>

pimd/pim_rp.c

@@ -404,6 +404,7 @@ pim_rp_new (const char *rp, const char *group_range, const char *plist)
             return PIM_RP_NO_PATH;
 
           pim_rp_check_interfaces (rp_all);
+	  pim_rp_refresh_group_to_rp_mapping();
           return PIM_SUCCESS;
         }