Update Royal Circuit doc

hardware/ecp5_mainboard/mainboard_prod/readme-royalcircuit.txt

@@ -1,7 +1,9 @@
 TrellisBoard rev1.0
 --------------------
 
-Contact: David Shah <dave@ds0.me>
+Fork Sand, Inc. fork/clone.
+
+Contact: Jeff Moe <moe@forksand.com>
 
 Files:
  - gerber/: gerbers for all layers
@@ -14,10 +16,11 @@ Files:
         PTH: plated holes drill
  - part_mapping_top.svg, part_mapping_bottom.svg: graphical part mapping (copy of silkscreen)
  - ecp5_mainboard-all-pos.csv: x & y coordinates for all SMD parts
- - ecp5_mainboard_bom_elecrow.xls: bill-of-materials for all parts
+ - ecp5_mainboard_bom_royalcircuit.ods: bill-of-materials for all parts in LibreOffice format
+ - ecp5_mainboard_bom_royalcircuit-export.xls: bill-of-materials for all parts exported to XLS format
 
 BOM notes:
- - Turnkey order, all parts to be ordered by Elecrow
+ - Turnkey order, all parts to be ordered by Royal Circuit
  - Parts with "Substition Allowed" = N must be exact part number match from a distributor (DigiKey, Mouser, etc). DigiKey part numbers are typically given but other distributors may be used
  - Parts with "Substition Allowed" = Y may be substitued with parts of an equal or better specification from another manufacturer/distributor.