client: incorrect partition type conversion to hexadecimal

partition code is already in decimal as integer, appending 0x to this decimal
results in an incorrect hexadecimal conversion when storing it to the database.

The web frontend bogusly displays "Empty" as partition type until a refresh
happens.

src/client.c

@@ -693,7 +693,7 @@ static bool og_update_client_disk_info(struct og_dbi *dbi,
 							"idordenador, numdisk, numpar, codpar, tamano, uso, "
 							"idsistemafichero, idnombreso, idimagen, "
 							"used_size, free_size)"
-							" VALUES(%d,%s,%s,0x%d,%s,0,%d,%d,0,%lu,%lu)",
+							" VALUES(%d,%s,%s,%d,%s,0,%d,%d,0,%lu,%lu)",
 							computer_id,
 							partitions[i].disk,
 							partitions[i].number,