[m-rev.] diff: fix bootcheck in C#

[Zoltan Somogyi]

With these changes, bootcheck can build stage 3.

Zoltan.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Log.gl2
Type: application/octet-stream
Size: 287 bytes
Desc: not available
URL: <http://lists.mercurylang.org/archives/reviews/attachments/20200416/8b88a3c9/attachment.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: DIFF.gl2
Type: application/octet-stream
Size: 1408 bytes
Desc: not available
URL: <http://lists.mercurylang.org/archives/reviews/attachments/20200416/8b88a3c9/attachment-0001.obj>