Fix compile failure

Improper const was added in 804077 to one of the variables
used as a parameter to mapper_get_service.

Change-Id: I29eeb255794af381c48b505e12a7d68db6d5c54a
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/writefrudata.C b/writefrudata.C
index bccaf0a..8a34e6e 100644
--- a/writefrudata.C
+++ b/writefrudata.C
@@ -171,7 +171,8 @@
     int rc = 0;
 
     // What we need is BOARD_1, PRODUCT_1, CHASSIS_1 etc..
-    const char *inv_bus_name = NULL, *inv_obj_path = NULL,
+    char *inv_bus_name = NULL;
+    const char *inv_obj_path = NULL,
                *inv_intf_name = NULL;
     char fru_area_name[16] = {0};
     char *sys_bus_name = NULL;
@@ -237,6 +238,7 @@
 #endif
 
     free(sys_bus_name);
+    free(inv_bus_name);
     sd_bus_error_free(&bus_error);
     sd_bus_message_unref(response);