RSB checksum updates for RTEMS 6

[Chris Johns]

Hi,

I have opened https://devel.rtems.org/ticket/4991 to track checksum errors in
some of the sources being downloaded by the RSB such as:

error: checksum failure file:
patches/Make-lang.in-b09fb02bb4c0d16fc2c842bec4069c033897b5f2.patch

I am seeing this error while I attempt to create 6.1-rc2. I am asking if it
would be OK for me to push changes to the RSB under this ticket without review
while I sort this out?

Thanks
Chris